Police tape line. (QMI Agency/CRAIG GLOVER)

Police in New Brunswick are investigating the death of a 43-year-old man who died in custody after being arrested twice Sunday.

The suspect was first arrested around 4 a.m. after police received complaints that a drunk man had been knocking on people's doors. He was released shortly before noon, but picked up again three hours later when someone reported the man allegedly tried to break into a house.

Police said Mounties were following the RCMP's policy of checking on suspects in custody every 10 to 15 minutes when a guard found the man "unresponsive" at 9:25 p.m.

He was given CPR on the scene, then taken to hospital, where he was pronounced dead.

Police have not released the identity of the man but have said he is from Tracadie-Sheila, N.B. An autopsy will be conducted to determine the cause of death.