Several police investigations are underway in Solomon Islands after a young man died in police custody over the weekend.

The 23 year old man had been in the cells since his arrest last Friday night and police say he was found dead in his cell on Monday morning.

The police says the matter is serious and are asking people to refrain from speculating on the cause of death.

A post mortem is being conducted.

They say investigations are being conducted by Professional Standards and Internal Investigations, the National Criminal Investigations Department and officers from the PPF.