A 21-year-old man will face court tomorrow accused of murdering a police station cleaner.

Detectives announced tonight they had charged the man with murdering Enayit Khalili 14 months ago.

However they have refused to release the man's name or any other identifying details until he appears before Oxford magistrates tomorrow morning.

Mr Khalili was found severely injured at his home in Fiennes Road, Rose Hill, Oxford, around 3.30am on the 24 March 2007. He died that evening from a single stab wound to the stomach.

A woman in her 60s arrested on suspicion of perverting the course of justice has been released on police bail while further enquiries are made, police spokesman Victoria Bartlett said.

The pair were arrested on Friday and were questioned over the weekend.

Thames Valley Police usually release the name and address of those charged but Miss Bartlett said officers would not do that in this case.

Mr Khalili worked as a cleaner at Cowley police station in the city.

Born in Afghanistan, he came to Britain in 2001 seeking asylum. He received permanent leave to remain in the country in the months before he was murdered.

A £25,000 reward was offered for information leading to the conviction of his killer.

The man charged will appear before magistrates tomorrow, when the case will almost certainly be committed to Oxford Crown Court.