At least 16 people, most of them children, burned to death and another 14 were injured when a bus caught fire in the northern Colombian town of Fundacion, authorities said.

The police commander for Magdalena province, where the accident occurred, Col. Adan Leon, gave Noticias Caracol the preliminary casualty count while investigators were still examining the scene.

"We are talking of 16 fatalities. We have not finished the inspection," said Leon, who added that the 14 injured people had been transported to nearby hospitals.

Leon said that the incident occurred when a group of more than 30 children who had left worship service at the local Pentacostal Church boarded the bus to return to their homes and the vehicle "caught fire and resulted in the loss of a number of lives."

Colombian President Juan Manuel Santos, who on Sunday was focusing on the logistics of wrapping up his re-election campaign on May 25 in Bogota neighborhoods, said on his Twitter account that he deplored the incident.

"We deeply regret accident in Fundacion, Magdalena, where according to latest information at least 15 people died, including children," the president said.

The death toll could rise, given that Fundacion Mayor Luz Stella Duran told Caracol Radio that 26 people had died.

Meanwhile, National Police commander Gen. Rodolfo Palomino told reporters that the initial hypothesis investigators are considering is that "apparently, a mechanical failure caused the fire inside the bus." EFE