THREE Royal Marines arrested in connection with the murder of a Navy rating who died following a fight in a bar remain in custody tonight.

Engineering Technician (Marine Engineering) Kyle Bartlett was found with serious injuries following an altercation inside the Walkabout bar in Guildhall Square, Portsmouth, Hampshire, at 11.05pm on Tuesday.

The 21-year-old junior rating was taken by ambulance to the Queen Alexandra Hospital in Portsmouth, where he died yesterday evening, according to police.

A post-mortem examination carried out today revealed ET (ME) Bartlett died as a result of head injuries.

Four men, three aged 21 and one aged 22, all Royal Marines, were arrested in connection with the incident.

Another man, aged 26 and from Portsmouth, was also arrested on suspicion of murder, but was this evening released without charge. Police have not confirmed whether he is a member of the Armed Forces.

Earlier, the 22-year-old was also released without charge, while the other three remain in custody to be questioned on suspicion of murder.

A Royal Navy spokesman said: ''I can confirm that a number of naval service personnel are assisting Hampshire Police with an investigation into an alleged incident.

''This is a Hampshire Police investigation and so it would be inappropriate to comment further at this stage.''

Tributes have begun to be left for ET (ME) Bartlett on the Facebook social networking site.

Stuart Walls wrote: ''Gone but never forgotten. You had a heart of gold shipmate my thoughts are with your family.

''Rest in peace big man.''

ET Bartlett's page states that he was a member of a group for people who had served aboard HMS Liverpool, a Portsmouth-based Type 42 Destroyer.

It also states that he was educated at Mill Chase Community College in Bordon, Hampshire.