Passengers suffered massive delays after the bird flew into the Virgin Voyager's overhead power system, it emerged on Wednesday.

The problem, on the West Coast Main Line in Staffordshire, was made worse when the rescue train broke down, blocking other trains.

Virgin has offered passengers affected by the problems, which occurred on 3 July, free first class return tickets.

We found the remains of a very large bird, but it was so badly burned we couldn't tell what it was

Alan McLean

Hundreds of travellers on the Virgin train, and two other trains behind it were stranded near Penkridge, Staffordshire.

Engineers found a bird wedged in a roof recess holding conducting equipment.

They had to wait until the early hours before emergency repairs were finished to allow the Manchester train to complete its journey to Birmingham.

Spokesman Alan McLean said investigators had been unable to establish what kind of bird was to blame for the fault.

He said: "We found the remains of a very large bird, but it was so badly burned we couldn't tell what it was.

"We think it could have been a pigeon or a crow."

Mr McLean said the problem had a knock-on effect on the rest of the train's electrical system, including lights and catering equipment.

Hours late

There was further trouble when the rescue train suffered a mechanical fault on route, which delayed the repair operation.

The train eventually arrived at Birmingham New Street more than seven hours after the bird flew into it at 1700BST.

Mr McLean said Virgin had since written to 150 passengers for whom it had names and addresses offering them two complimentary first class return journeys to any destination in the country.

Customers who contacted the firm would also be offered the same gift, he said.