At least 61 people were killed in a stampede following a New Year fireworks display in Abidjan, Ivory Coast's commercial centre, officials said.
The death toll is expected to rise, according to rescue workers.
The majority of those killed were young people aged between eight and 15 who were trampled after the festivities in Abidjan's Plateau district, at about 1am local time on Tuesday, said Colonel Issa Sako, of the fire department rescue team.
Thousands had gathered at the Felix Houphouet Boigny Stadium to see the fireworks and after the display the crowds moved out on to the Boulevard de la Republic near the Hotel Tiama, said Col Sako, on Ivory Coast state television.
"The flood of people leaving the stadium became a stampede which led to the deaths of more than 60 and injured more than 200," he said.
President Alassane Ouattara has visited some of the injured in hospital and pledged that his government would pay the costs of their medical treatment, according to his office.
Mr Ouattara's government organised the fireworks to celebrate Ivory Coast's peace, after several months of political violence in early 2011 following disputed elections. It was the second year that Abidjan had staged a New Year fireworks display.
Desperate parents went to the city morgue, the hospital and the stadium to try to find children who are still missing.
Mamadou Sanogo was searching for his nine-year-old son, Sayed.
"I have just seen all the bodies, but I cannot find my son," he said tearfully. "I don't know what to do."