MILWAUKEE (CBS 58) -- An investigating is underway after a 20-year-old man attempted suicide while being held at a Milwaukee Police Department. 

Authorities say on Thursday, Nov. 7 officers conducted a traffic stop near 41st and Locust, and an arrest was made after narcotics were found on the suspect and vehicle. 

The suspect was taken to MPD District 7, located at 3626 West Fond Du Lac Avenue, for prisoner processing. 

During a routine check, police say an officer observed the suspect unresponsive and hanging in the cell.

Several officers responded and provided first aide. The 20-year-old Milwaukee man was transported to a local hospital in critical condition.

As protocol, the Milwaukee Area Investigative Team is investigating the incident as the man’s injuries are life threatening.

The Waukesha Police Department is the lead investigating agency in the ongoing investigation.