POLICE have arrested another man following the murder of a drug addict on Teesside.

Officers investigating the death of 29-year-old Robert Parkin, who was found dead in a top-floor flat in Shaftesbury Street, Stockton, have been involved in a series of operations in a bid to track down people believed to be involved.

One involving the police helicopter, aeroplane and a number of police cars was centred on the Riverside in Stockton on Wednesday night.

It resulted in the arrest of a man, the fifth person to be taken into custody. He is being questioned by police at Stockton Police Station.

This morning there were also several raids on houses and other premises throughout the Stockton area for an outstanding suspect.

Four people, including two women, were arrested earlier this week. Of those one woman and one man have been released on police bail.

The other couple have also been given police bail but were charged with a series of drug offences and were due to appear at Teesside Magistrates Court this afternoon.

Detective Superintendent Mark Braithwaite, who is heading the inquiry, said they are now concentrating on the hunt for a man who is known to the police.

He said "We have carried out a number of raids which so far have failed to locate this man and we will be continuing our operations to trace him.

"There will be no let up in our hunt for this individual and more raids will be carried out until we find him."