A judge has extended the period a man arrested in connection with the death of a teenage girl in Barkingside can stay in custody.

The 21-year-old was arrested on Tuesday night after a 17-year-old girl was found dead in a flat above the Buy Labels For Less clothes store in High Street.

A post-mortem carried out on Wednesday found she was strangled.

Police who arrested the man in connection with their investigation had to apply to a judge for a warrant of extension on Thursday morning – 36 hours after he was arrested.

A further 12-hour extension was given to police on Thursday night.

A third extension is expected to be sought by police this morning.

The man can be held in custody for up to 96 hours – four days – before he must be charged, bailed or released.

Police say they believe they know the identity of the girl and have informed her next of kin, but are waiting for formal identification.

London Ambulance Service paramedics found her alive, but she died shortly after.

Police say they were called to the flat after reports of a “disturbance”.

The post-mortem was held at Walthamstow Mortuary.

An inquest is due to open and adjourn at Walthamstow Coroner’s Court in the next few days.

An incident room has been set up under the command of Acting Det Ch Insp John Nicholson of the Metropolitan Police Service’s Homicide and Serious Crime Command at Barking.

Anyone with information should contact the incident room on 020 8345 3985, or Crimestoppers anonymously on 0800 555 111.