A 38-year-old man died Friday afternoon after a struggle with D.C. police officers who were sent to an address in Southwest Washington to assist personnel from the Department of Mental Health, police said.

The man, identified as Anthony Chambers, assaulted four officers after they arrived at an apartment in the unit block of P Street SW, police said.

After being subdued and handcuffed, police said, Chambers lost consciousness. He was taken to a hospital, where he died, police said. They said an autopsy would be done to determine the cause of death.

Police said the four officers were injured.

Tiffany Chambers, who said she was Chambers’s niece, denied that he had mental health problems. She said relatives were trying to find out why police were called.

“They just beat him to death for no reason,” she said.

A 16-year-old who said he was Chambers’s nephew said his uncle had an asthma attack. No address was available for Chambers.

A Department of Mental Health spokeswoman confirmed that staff members went on Friday to the address where the incident occurred and that police were summoned in keeping with departmental procedures.