Nearby businesses were evacuated after a freight train derailed in Boulder, Colorado. Authorities ordered the evacuation which lasted an hour while they determined whether the carriages contained any hazardous materials.

"A train has just de-railed. Haz-Mat is en route. We hope to have more info shortly," the Boulder Police Department tweeted just after the incident. "Businesses within 100 yards of the derailment are being evacuated out of precaution. We do NOT yet know if the train was carrying hazmat."

A number of roads where closed for some hours while authorities investigated the scene.

Officials later said that the spilled materials "do not appear to be hazardous," adding that the "train car was full of plastic beads which are not hazardous. Evacuations are being lifted now."

Footage from the scene showed firefighters attending the train, which came completely off the tracks and was lying lengthways across the rail.

The cause of the derailment remains unclear and it was not known whether there are any injuries from the incident.