Maui police arrested a Wailuku couple today after the man’s 4-year-old boy was taken to the hospital with severe injuries and died five hours later.

Police said the 31-year-old father brought his son to Maui Memorial Medical Center about 10:57 p.m. Tuesday after allegedly finding the boy unresponsive in the shower.

An initial exam by emergency room doctors found the boy had sustained severe blunt force trauma to his internal organs and died of his injuries, police said.

A Maui coroner’s official said the boy died at the hospital at 4:33 a.m. today. An autopsy is scheduled for tomorrow.

The father and his 27-year-old live-in girlfriend both denied having any knowledge of how the boy sustained his injuries.

They turned themselves in at the Wailuku station about 11 a.m. today and were arrested for investigation of second-degree murder.