An off-duty police officer was assaulted after trying to break up a fight on a Shenfield train.

British Transport Police are appealing for information about the incident on Sunday, May 4, when the officer was returning home on the 12.50am London Liverpool Street to Southend Victoria train.

As the train approached Shenfield station there was an altercation between a group of men.

The victim said he was a police officer and tried to break the fight apart, but as a result he was assaulted by one of them, who punched him in the back.

The men left the train as it arrived into Shenfield station at about 1.20am and ran from the station.

Officers are investigating and will be viewing CCTV from on board the train, station and surrounding area. Police are also urging anyone who was on the train and who saw the incident to come forward.

PC Ian Anderson, the investigating officer, said: “We believe there may have been other people injured from the fight who have not yet identified themselves. If you were on board the train, and have not contacted police yet, I’d urge you to get in touch.”

They are particularly keen to speak to two men, who are believed to be in their 20s. The first man was of slim build, 5’8” tall, had light brown wavy hair with highlights and was wearing a grey top.

The second man was around 6’ tall, medium build and had short brown hair. He was wearing a white polo t-shirt.

Anyone with information is asked to contact British Transport Police on 0800 40 50 40 quoting background reference B4/LNA of 22/05/2013 or you can call Crimestoppers anonymously on 0800 555 111.