Dallas police looking for answers on how a man found with a puncture wound died

Dallas police are investigating how a man found with a puncture wound ended up dead at a local hospital.

Authorities say Dallas Fire‑Rescue units were called to Central Expressway south of Mockingbird Lane just before 12:30 a.m. Thursday, after a witness saw a man in distress and believed he might have been hurt.

The man was taken to a hospital, where he later died.

"The motives and circumstances surrounding this incident remain under investigation," police said in a news release. "This case is currently documented as an unexplained death."

The Dallas County Medical Examiner's Office will determine the cause of death and work to identify the man, police said.

CBS News Texas will provide updates as more information becomes available.