Armed with a gun, Clint Engle of suburban Plainfield entered a West Loop dental office looking for his girlfriend before fatally shooting himself Thursday. View Full Caption Illinois Department of Corrections; DNAinfo/Stephanie Lulay

WEST LOOP — A man carrying a shotgun who went to his ex-girlfriend's West Loop workplace looking for her before before killing himself Thursday had a history of domestic violence, court records show.

The man was identified by the Cook County Medical Examiner's Office as Clint Engle, 40, of southwest suburban Plainfield. He entered the dental office, Skyline Smiles at 1017 W. Madison St. around 11 a.m. Thursday, prompting the former girlfriend to flee to an alley, Chicago police said.

In 2002, Engle was found guilty of felony home invasion and aggravated battery after beating the father of a woman he was dating with a golf club, according to the Joliet Herald-News. Engle eventually served 12 years in prison, according to Illinois Department of Corrections records.

Listen to Stephanie Lulay describe what happened at Skyline Smiles.

RELATED: Movers Hid Woman in Truck as Armed Ex Searched for Her at Dental Office

In the January 2002 case, Engle broke into a Joliet home where the woman's father was sleeping, cut the telephone line and then beat the man on the head. Engle was angry because he believed that the father would not allow him to date the daughter, according to court records.

During the beating, Engle reportedly told the father, "You're going to die for not letting me go out with your daughter."

The victim's head injuries required more than 50 staples, police said at the time.

Engle also was investigated for smashing a window in a former girlfriend's suburban Crest Hill apartment after seeing her with her new boyfriend. He reportedly jumped through a window, wrestled the boyfriend and then struck the woman twice, according to the Herald-News.

Engle was released on parole in October 2014, according to Corrections Department records. He was slated to be discharged from parole in October 2017.

As Engle searched for his ex-girlfriend at the dental office Thursday, a group of movers may have saved her life by helping her hide in their truck.

On Thursday, Skyline Smiles Dr. Deepak Neduvelil said his staff was trying to focus on healing.

"It was a truly traumatic thing that happened. We are really just trying to cope, and are so thankful that we are safe," he said.

Gun suspected stolen

Engle may have stolen a firearm from a Plainfield home earlier in the day.

At 9:43 a.m. Thursday, the Plainfield Police responded to a residential burglary in progress in the 23000 block of Ottawa Street, according to a news release.

Before police arrived, a man removed a firearm from the home and fled the scene. Police began to search the area and several area schools were placed on "soft lockdown" as a precaution.

The suspect, who sources say is Engle, was eventually found dead on the Near West Side in Chicago, according to Plainfield Police. Plainfield Police continue to investigate the burglary.

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