The fault was spotted by a maintenance team on the East Coast main line at Conington near Peterborough in Cambridgeshire at 0918 BST on Tuesday.

Several trains were delayed and some were cancelled altogether on Tuesday morning.

It was a broken rail which caused the derailment of a train at Hatfield in Hertfordshire in October 2000, which killed four people.

Track closed

On Tuesday four East Coast trains heading to London were left stranded before being allowed to proceed at 5mph.

The stretch of track was then closed off, and further southbound trains used one of lines usually used by northbound services.

The broken rail was removed and replaced by about 1300 BST.

Great North Eastern Railways said services were running normally shortly afterwards.

A Railtrack spokeswoman said: "A track maintenance patrol spotted a rail that was cracked."

She added that East Coast services had already been disrupted by the collapse of overhead wires near Berwick in Northumberland.