A 25-STRONG mob terrorised a railway station and passengers on an express, setting off fireworks and abusing anyone who challenged them after a day's heavy drinking on a stag weekend.

The group, chanting football terrace songs, had already attracted police attention in York city centre, although none had been arrested.

But after arriving at the station, their behaviour became more reckless.

A ''jumping jack'' firework was thrown into the Whistlestop sandwich shop, where the screams of customers frightened by the explosions were greeted with a drunken cheer.

Another was left at the door of the nearby Coopers bar with much the same result, as well as setting off fire safety devices, which closed the premises for 15 minutes.

The stag party boarded a Virgin train to return to Leeds but, alerted by the incidents at York station, two British Transport Police officers decided to follow them - and were greeted with a torrent of abuse.

''The language was disgraceful, seeing as there were families in the next carriage compartment,'' said PC Kevin Andrews yesterday. ''I've dealt with worse but it was intimidating for the other passengers and it was while I was trying to reassure them that another firework was thrown down the aisle.''

The explosions terrified young children travelling with their parents but, when PC Andrews challenged the culprit to identify himself, it prompted further abuse and jeering.

''It was sickening,'' he said. ''These were not youngsters but grown men in their 30s and 40s who probably have families themselves.

''However, in the circumstances, it would not have been a good idea to try to arrest anyone there and then; we would have been putting ourselves in danger and could have made the situation worse.''

When the train arrived in Leeds, British Transport Police were able to reinforce PC Andrews and Special Constable Michael Dawes, and a number of people were arrested.

Since the incident on Saturday evening, one man has been charged with public order offences as well as another under the 1875 Explosives Act and will appear at York Magistrates Court on Friday.