BOGOTA, Colombia (AP) — An overcrowded bus carrying young people home from a church service caught fire on a street in a northern city Sunday and at least 32 children were killed, authorities said.

The regional police chief, Col. Adan Leon, said 18 people, including some adults, had been found alive at the disaster in the city of Fundacion, which is about 750 kilometers (465 miles) north of Bogota. He said information was not complete and he warned that the death toll could rise.

Leon said most of the estimated 50 people on the bus were younger than 14. “That adds to the tragedy,” he said.

Local officials said the bus was rated to carry only 38 passengers and an investigation was underway. Mayor Luz Estella Duran told RCN television news that investigators had not yet determined what caused the fire.

Officials said the people on the bus were returning from an event at an evangelical Christian church.

President Juan Manuel Santos, who was attending campaign events in Bogota a week before Colombia’s presidential election, announced that he would travel to Fundacion.

Copyright 2014 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.