Portsmouth murder probe: what we know so far

The murder investigation was launched after Ollie Blatcher, 18 from Buckland, was found injured in Sackville Street, Southsea on Saturday.

Paramedics were called to Sackville Street at around 1.54am, with the man dying later in the day at Queen Alexandra Hospital in Cosham.

Exact details of the incident are currently unknown, with investigating police saying that the post-mortem result was 'inconclusive'

A police spokeswoman said: 'A post mortem examination has been carried out, however the findings are inconclusive. Further tests will be carried out.

'Detectives continue to work hard to establish the exact circumstances surrounding the man's unexplained death, and the investigation is on-going.'

Two men arrested on suspicion of murder have been released but remain under investigation.

The police spokeswoman added: 'A 28-year-old man and a 32-year-old man who were arrested in connection with the death have been released from custody, but remain under investigation.'

Friends and family have paid tribute to Ollie following his death.

On Sunday afternoon, a group of teenagers gathered outside a block of flats in Sackville Street - with the crowd of people rapidly growing.

Colourful flowers filled the pavement, with balloons filled with messages and fond nicknames launched into the sky later in the day.