CLINTON, Iowa — An armed man is in custody after taking two hostages Sunday night at a Clinton grocery store.

He voluntarily surrendered to police about 9:30 p.m. Sunday after releasing one hostage about 20 minutes before he gave himself up to police. The other hostage, believed to be a former girlfriend, was released when the armed man surrendered.

The suspect, who is believed to be about 20 years old and from Clinton, entered the Jewel-Osco grocery store, 1307 N. 2nd St., about 6:30 p.m. Sunday. He then took a man and a woman hostage, according to Capt. Mike Gertson of the Clinton Police Department said.

Police have identified neither the suspect nor the victims, but the suspect is believed to be a former employee at the grocery-drug store. He appeared to have self-inflicted cuts that are not life-threatening, Gertson said, and he was taken to Mercy Medical Center in Clinton.

The suspect had an employee set off the fire alarm to clear the store of other customers and employees, police said.

About 20 law enforcement personnel, including hostage negotiators and the regional Hazard Entry Approach Team, or HEAT, were on the scene. About 9:10 p.m. a HEAT negotiator was able to mediate the release of the male hostage, who is believed to be a 20-year-old employee of the store, Gertson said.

Police believe the suspect was texting via cell phone with a person outside the store. Police also said a shot was fired in the building but that it apparently wasn’t aimed at anyone.

“I feel good. Everybody’s out safe,” Gertson said.

This is the second hostage situation in Clinton in the last month. Shamus B. Pridemore, 39, of Fulton, Ill., took his wife hostage for six hours before taking his own life April 13 at the Iowa Workforce Development office in Clinton.

Gertson said law enforcement discussed the April incident and worked out ways to improve their response.

In January, a Clinton man held his four children hostage after arguing with his wife. No one was injured.

The HEAT team is a tactical response unit made up of officers from the Clinton County Sheriff's Office and police departments from Clinton, Camanche, DeWitt and Fulton, Ill.