Fire officials in the US state of Maryland have said a cargo train crashed into a trash truck, causing an explosion that rattled homes at least a half-kilometre away and collapsed nearby buildings.

The crash, near Baltimore on Tuesday, also set buildings on fire and caused 51 cars of the train to derail, according to John J. Hohman, the country fire chief.

"We will tell you first of all there is no evidence of any toxic inhalants. Our fire department folks have not ordered any evacuation," said Kevin Kamenetz, Baltimore County Executive.

"We have as a precaution through reverse 911 requested individuals who are within a 20 block radius just to stay out of the area," he added.

The cause of the explosion is being investigated, and emergency crews and hazardous material specialists are at the scene.

The explosion sent up a thick plume of smoke that was visible for miles.

Kamenetz also said the truck driver was in serious but stable condition at a hospital. No other injuries were immediately reported.

The train was en route to Waycross, Georgia from Selkirk, New York.

Source: Agencies