A rush hour train packed with dozens of commuters derailed in Liverpool (search) on Wednesday, police said. No injuries were immediately reported.

The underground train, thought to be carrying about 90 passengers, came off the track about 6 p.m. as it traveled toward the city's Central Station, according to the British Transport Police (search). The local ambulance service said it hadn't received any reports of injuries.

Merseyside Fire Service (search), which covers the Liverpool region, said a search and rescue team was at ene and was helping passengers off the train.

The regional police said the cause of the derailment, which occurred between the Moorfield and Central stations, was not known.

Police and ambulance officials said no injuries had been reported.