An independent investigation is under way in the case of a 26-year-old man who died after Tukwila, Wash., police tried to take him for an involuntary mental health commitment.

Tukwila Sgt. Mark Dunlap says police responded Saturday to a 911 call from family members who said the young man "with a history of mental illness" was being combative and making strange statements.

Officers found the man holding a golf club and threatening his family.

Dunlap says the man broke an ankle trying to escape from officers as they were taking him into custody. They called for medics and an ambulance. Police say the man began having trouble breathing in the ambulance. He was taken to Seattle's Harborview Medical Center, where he died. The cause of death has not been determined.