(CNN) -- Somalia's president on Wednesday declared three days of national mourning for the victims of a suicide truck bomb that killed more than 70 people in Mogadishu, the nation's capital.
According to the Health Ministry, 72 were killed Tuesday and 103 remained injured, 38 of those in serious condition. A majority of the victims were students and their parents who were registering for an education program at a government complex.
Al-Shabaab, an Islamist movement that has links to al Qaeda, claimed responsibility.
President Sharif Ahmed visited the scene and some of the hospitals where the victims were, the government said in a statement. Some of the injured who cannot be treated in Somalia will be flown to other countries.
"At this time, when the country is in the midst of a worsening humanitarian crisis, the terrorists could not have attacked the Somali people at a worse time," said Abdulkadir Hussein Mohamed, the country's minister of information.
According to the government, Tuesday's bombing was the second Al-Shabaab attack in two years that specifically targeted students. In December 2009, a suicide bomber attacked a university graduation ceremony in Mogadishu, killing more than 20 people.
Al-Shabaab is a group in Somalia that was designated as a foreign terrorist organization by the United States government in March 2008. It is waging a war against Somalia's government to implement a stricter form of Islamic law, or Sharia.
Federal and African Union forces in the impoverished and chaotic nation have battled the group for years. Many analysts believe that Al-Shabaab has been severely weakened by the African Union Mission in Somalia, targeted strikes against foreign members and the weakening of al Qaeda.