The assassination of Haiti’s President Jovenel Moise has stunned the country and shocked regional leaders. The Caribbean nation of roughly 11 million people, many of them living amid poverty and rising violence, now faces an even more uncertain future. Haiti’s acting Prime Minister Claude Joseph has assumed leadership of the country in the immediate aftermath of the attack. He declared a “state of siege” in Haiti – closing the country’s borders and imposing martial law – saying he did not want the nation to “plunge into chaos.” What exactly happened to Moise? Authorities have said a group of “professional killers” stormed Moise’s private residence in Petion-Ville, a suburb of Haiti’s capital, Port-au-Prince, at around 1 a.m. Wednesday. Moise was shot 16 times, former Haitian Prime Minister Laurent Lamothe said. The President was aware of a possible assassination threat and that was why in recent months he was rarely seen outside of his home, Lamothe told CNN. Haiti’s first lady, Martine Moise, was also shot in the attack and was evacuated to a hospital in Miami, Florida, for treatment. Haiti’s ambassador to the United States, Bocchit Edmond, said he believes the first lady is “now out of danger.” Jovenel Moise, who was 53 and a former banana exporter, had spent most of the past year waging a political war with the opposition over the terms of his presidency. What’s known about the attackers? Police have so far arrested 20 suspects over the fatal shooting and a mass, countrywide manhunt is underway for at least five more suspects. Police previously said 28 people were suspected in the assassination. Citing figures from Haitian police, the office of Joseph told CNN that three suspects were killed in a shootout with authorities after the attack. On Friday, police published a list of the names of 19 suspects who had been apprehended by authorities, which they said included 17 Colombians and two Haitian-Americans. Shortly afterward, police announced that an additional Colombian suspect had been arrested. Thirteen retired members of the Colombian Army, all believed to be involved in Moise’s assassination, traveled to Haiti over the past months – almost all of them through the Dominican Republic – Colombian National Police Chief General Jorge Vargas told a press conference on Friday. But even as more details begin to emerge of the people who allegedly killed Moise, little is known about the suspected masterminds and their motivation for the attack. What’s the broader situation in Haiti? Moise’s death comes against a backdrop of political instability, with many key roles in the country’s government already empty and the parliament effectively defunct. Haiti’s opposition movement has long called for Moise to resign. Amid heightened tensions in the wake of the assassination, crowds of people took to the streets Thursday night, burning cars and demanding justice. Criminal violence has recently escalated in capital Port-au-Prince, including targeted attacks on police and arson of civilian homes. Infamous ex-police officer Jimmy Cherizier vowed in June before local media to carry out a “revolution” in the city. That month, more than 13,000 people fled their homes in Port-au-Prince for temporary shelters, according to the United Nations. The insecurity follows a wave of kidnappings earlier this year. Battles between rival groups and the police for control of the port city’s streets have also worsened the country’s humanitarian crisis, threatening bottlenecks on food and fuel supplies. Meanwhile, Covid-19 is spiking in Haiti, which is one of only a few countries across the globe not to have yet started vaccinating against it. Pan American Health Organization Director Dr. Carissa Etienne last month called on the international community to “urgently” assist the country in combating the virus. The White House has said vaccines are being sent from the US and could come “as early as next week.” Why was Moise controversial? Many in Haiti disputed Moise’s right to continue serving in the presidency this year. He said his five-year term should end in 2022 – a stance backed by the United States, United Nations and Organization of American States. But the opposition – which accused Moise of allowing corruption and insecurity to flourish in the country – argued that he should have stepped down on February 7 this year, citing a constitutional provision that starts the clock on the term once a president is elected, rather than when he takes office. Moise’s inauguration was delayed over allegations of voter fraud during the 2015 election, which led to a presidential runoff that was postponed twice over what authorities called threats and “security concerns.” During his presidency, Moise repeatedly failed to hold elections at local and national levels, leaving much of the country’s governing infrastructure empty. A constitutional referendum is set to be held in September, alongside the presidential and legislative elections. The referendum had been championed by Moise as an opportunity to strengthen the Haitian presidency. Municipal and local elections have been scheduled for January 16, 2022, the official electoral calendar also showed. Who takes over from him? It isn’t immediately clear who will replace Moise in the coming months. Judge Jean Wilner Morin, president of the National Association of Haitian Judges, told CNN that the line of presidential succession in the country was murky given its political instability. Haiti’s President of the Supreme Court would normally be next in line, but that position is currently empty since its holder, René Sylvestre, recently died of Covid-19. For the acting Prime Minister Joseph to formally replace the President, he would have to be approved by Haiti’s parliament, said Morin. But the parliament is currently partially empty and effectively defunct. Muddying the waters further, Joseph was in the process of being replaced by Ariel Henry, whom the President appointed shortly before his death. Henry told the Haitian newspaper Le Nouvelliste that “Claude Joseph is not prime minister, he is part of my government.” There is another possible succession scenario, too, said Morin. “The precedent is that in 2015, it was the President of the National Assembly who replaced the President of the Republic. Today we don’t have a President of the National Assembly, but there is still a third of the Senate in Parliament and the third of the Senate is presided over by a former senator, named Joseph Lambert.” In a statement issued Wednesday, the acting Prime Minister Claude Joseph appealed for calm. “The security situation in the country is under the control of the Haitian National Police and the Haitian Armed Forces,” he said. He also called on the international community “to launch an investigation into the assassination and for the United Nations to hold a Security Council meeting on Haiti as soon as possible.” Joseph later asked the UN to deploy troops to help secure the country’s ports, airports and oil terminals. In addition, he asked the agency for assistance with electoral security and to help further investigate the assassination. What’s the humanitarian situation in Haiti? Haiti was already facing a dire economic situation before the Covid-19 pandemic hit. Its economy shrank a further 3.8% in 2020, with about 60% of the population now living in poverty, according to the World Bank. The recent spike in violence in the capital has only added to the troubles faced by many of its citizens, and complicated the work of aid groups such as Doctors without Borders and UNICEF, the UN children’s agency, in reaching vulnerable people. Bruno Maes, a UNICEF representative based in Port-au-Prince, told CNN last week that it is increasingly urgent that humanitarian workers be able to travel securely in the country as the peak of the Caribbean’s hurricane season approaches. UNICEF warned at the end of May that severe acute childhood malnutrition in Haiti was expected to more than double this year as it deals with rising violence, the coronavirus pandemic, and a lack of access to essential services, including clean water. More than 86,000 Haitian children under five could be affected, compared with 41,000 last year, the agency said. UNICEF also said acute malnutrition, which is somewhat less dangerous than severe acute malnutrition, had increased 61% over the last year. How will the United States respond? The United States is sending senior FBI and Department of Homeland Security officials to Haiti at the request of that country’s government – and Haiti has asked for several hundred US troops as well. White House press secretary Jen Psaki told reporters Friday the officials would travel to Port-au-Prince “as soon as possible,” and once there would assess the situation and provide assistance on security and the investigation. The Haitian government has asked for US troops to help protect infrastructure, ports, airports and energy systems, Haitian Elections Minister Mathias Pierre told CNN. Mathias said the request was for a limited number of about 500 troops and that he anticipated the threat to be “potential mercenaries.” The Pentagon said the Haitian government had “requested security and investigative assistance, and we remain in regular contact with Haitian officials to discuss how the United States can assist.” US State Department spokesperson Ned Price said the Haitian National Police had also asked for investigative assistance from the US, and it was responding to that request. Psaki on Wednesday called Moise’s assassination a “horrific crime” and pledged that Joe Biden’s administration would stand with the people of Haiti. In May, the Biden administration granted humanitarian protection for some Haitians in the United States, allowing an estimated 100,000 people to apply to remain lawfully in the country. The growing instability in the country could complicate upcoming decisions on future deportations of Haitians from the US.