NEW: The demonstration was peaceful for hours before clashes broke out
NEW: Some protesters threw rocks, Molotov cocktails in Mexico City's main square
The demonstrators hit the streets to demand justice for 43 missing students
Tens of thousands of protesters converged on Mexico City on Thursday to vent their frustration and anger over the disappearance of 43 college students, presumed by many to be dead, and widespread political corruption.
Students, union workers and supporters from around the country streamed into the Mexican capital’s main square, known as the Zocalo, for a demonstration that had been largely peaceful before ending in pitched battles between riot police and groups of protesters throwing rocks and Molotov cocktails.
Before these clashes, protesters marched into the square chanting “Justice! Justice!” They carried banners and hand-made posters featuring pictures of the students who disappeared at the end of September.
One group burned a giant doll resembling President Enrique Pena Nieto, who has come under fire for what some saw as his slow reaction to the students’ disappearance and for traveling abroad as protests spread across the country.
Others waved Mexican flags painted black to mourn the mostly poor, rural Mexicans who have disappeared or been killed in recent years amid the country’s drug violence.
“The problem isn’t just the 43 students, it’s the thousands more that disappeared before them,” said a vendor from the state of Mexico who traveled to the capital by bus to participate in the march. “We’ve ignored them for too long. We’re not going to be quiet any longer.”
The students, mostly young men in their 20s who been taking classes to become teachers at a rural school in the southern state of Guerrero, on September 26 had taken buses and vans to nearby Iguala for a protest.
Local police blocked the highway leading into the city and shot at the students’ vehicles, killing at least one student.
Officers took the remaining students away and, Mexican Attorney General Jesús Murillo Karam has said, handed them over to a local criminal gang known as Guerreros Unidos. That gang not only had infiltrated the police department but was also complicit with Abarca, his wife and the now-former police chief, according to the attorney general.
The gang burned the bodies and dumped them in a river, authorities say.
But the students’ families say they won’t believe the account until there is proof and a thorough investigation. At Thursday’s march, relatives led demonstrators in chanting, “They were taken away alive, we want them back alive!”
In the days leading up to the protests, the families had traveled around Mexico in three caravans seeking support.
The relatives also implored the backers to ensure the march was peaceful. When the protest showed signs of turning violent on Thursday night, they left.
In fact, peaceful speeches and marches marked the event’s first three-plus hours. But then a group of protesters – with their faces covered – clashed with police guarding the door to the National Palace that faces the Zocalo.
Many demonstrators panicked and ran to get away from the violence, leading to a stampedes. Others retreated, chanting “Justice!” and slowly counting from one to 43.
After a prolonged standoff with protesters throwing rocks and fireworks, hundreds of riot police swept across the Zocalo bearing shields and batons to clear out the area. Some of them used fire extinguishers against the protesters.
Mounting fury over government officials’ response to – and possible role in – the students’ disappearance has convulsed the country for weeks, posing a growing challenge to Mexico’s President amid demonstrations where at times violence has flared.
CNN’s Rosa Flores, Catherine E. Shoichet and Rey Rodriguez contributed to this report.