Police have requested the streets currently closed in Castletown will remain so until at least 4pm, while they carry out forensic investigations.
They're also continuing to appeal for witnesses to yesterday (Wednesday) evening's fight in the town which has left a man with serious head injuries.
The 42-year-old remains in a serious condition in hospital and a 35-year-old local man is in police custody.
The two-man fight happened at 6.15pm in Malew Street at its junction with Bank Street.
Inspector Derek Flint says they need to speak to people who saw what happened.
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