Thirty-one children were burned to death when their bus caught fire and exploded in northern Colombia on Sunday, the Red Cross said.

It was the deadliest road accident involving children in Colombia's history.

Another 25 people, including one adult, were injured and seriously burned in the blaze at Fundacion, Magdalena, said Cesar Uruena of the Colombian Red Cross.

"The injured have second- and third-degree burns, and many are still in critical condition" in hospitals in the area and in Santa Marta, Uruena said.

The children, between the ages 1 to 8, and were returning home on the bus after a religious service, Fundacion Mayor Luz Stella Duran told reporters.

Magdalena police said the bus exploded around noon and that the fire was so intense they had problems determining the number of casualties.

It was speculated the accident was related to fuel smuggling or misconduct by the driver.

A lot of Colombians smuggle cheap gasoline from Venezuela and transport it hidden in private cars and buses.

Major Eduardo Velez, coordinator of Magdalena province's emergency response corps, said there was a canister of gasoline inside the vehicle and the fire spread very fast.

Velez said the fire started after the driver attempted to start the malfunctioning bus by pouring fuel into the engine, which he accessed through the floor of the cabin. The driver escaped unharmed and was being questioned by police, he said.

But according to the mayor, the driver has vanished and angry locals went to his home and threw rocks at his windows.

Colombian President Juan Manuel Santos traveled to Fundacion.

"The entire country is in mourning for the death of these children," Santos said upon arriving in Fundacion, accompanied by his wife.

Santos said the government would pay for all hospital and funeral expenses relating to the accident.

The bus, which was being used by an evangelical church group, caught fire one block away from the church where the children had earlier attended services.

The Red Cross said it was sending four psychologists and two volunteer specialists in psychosocial aid to help the wounded and the relatives of the victims.

AFP-Xinhua

(China Daily 05/20/2014 page12)