Twenty students were seconds away from disaster yesterday as their school bus went up in flames immediately after they got off.

The teenagers from T.N. Tatem Middle School — on tour in California — were escorted off the bus went the vehicle caught fire due to a mechanical failure.

A teacher who was on the bus told The Royal Gazette they then stood at the side of the road and watched as the bus became engulfed in flames.

The educator praised the driver, who kept his head to steer the bus to safety across five lanes of highway, and the students and their chaperones, who were calm throughout.

"We must have struck a sharp object on the road, and then the bus caught fire," he told this newspaper.

"We were on the far right of the highway. Flames were already coming up the back of the bus.

"Initially, it was the driver who was skilful and wise enough to realise he had a serious problem. He was able to bring the bus to a stop fast enough.

"Then we got the children out and the chaperones off the bus and into a safe location, where we took cover under a bridge. The bus then became completely engulfed in flames.

"It was frightening for the children, but we have chaperones and we asked them to stay calm. While they were still on the bus, one or two were concerned, but we told them to be quiet and to listen to their instructions."

Nobody was injured, said the teacher. Asked how the students — aged about 13 — had reacted, he replied: "They are resilient. They now regard it as an adventure."

The incident happened at about 11 a.m. California time. The cultural trip was set to continue, with the party receiving a replacement bus.