MAQUOKETA, Iowa — An autopsy determined that a man died of “sudden cardiac arrest” after he was tackled while breaking into a Maquoketa business in March, officials said Wednesday.

The dentist who detained the man will not face criminal charges.

Police previously said Richard Purcell, 44, of Maquoketa, was breathing but unresponsive when law enforcement arrived at Overturff Dental Office, 204 Arcade St., on March 18. He later died at Jackson County Regional Health Center in Maquoketa.

Police said Dr. Clyde Overturff, of Dubuque, was staying overnight in the apartment at the dental office when he was awakened by a noise shortly after 2 a.m. March 18. He saw Purcell, yelled at the man and “tackled him in an attempt to restrain him.”

During the struggle, Purcell “slumped over and stopped fighting,” and Overturff called 911. Police previously said Purcell had a “medical episode” during the struggle.

On Wednesday, Jonathan Thompson, deputy chief medical examiner in the state medical examiner’s office, said an autopsy determined Purcell died from “sudden cardiac arrest following an altercation with and subdual by another individual” The manner of the death was “certified as a homicide.”

Earlier in the day, County Attorney Sara Davenport said via email that no criminal charges would be filed in connection to the incident.

Davenport said Purcell’s death “was the result of pre-existing medical conditions aggravated by the actions of the property owner who was defending himself and his property.”