DUPO, Ill. — The suspect accused of killing one man and injuring a police officer in the Metro East has a lengthy and violent criminal record.
Forty-year-old Reginald Allen was found dead in his garage after police said he shot and killed 46-year-old Darryl Mantz and injured a Dupo police officer in Dupo, Illinois on Sunday.
The department won't release the name of the officer shot, but as of Monday, police said he was stable, but in critical condition.
5 On Your Side learned the officer is 49 years old and has been in law enforcement for 12 years.
During a press conference on Monday at the St. Clair County Sheriff's Department Master Sergeant Brad Clossen said Allen was familiar with police.
"He's had a lengthy criminal history in St Clair County. Law enforcement in this area was very familiar with him," he said.
Sgt. Clossen said Allen is the man they believe is responsible for a homicide that ended in a 9-hour standoff in Dupo on Sunday.
"The St. Clair County investigators, along with the Illinois State Police investigators, began working this as a joint investigation," he said.
Police said it started around 1:30 p.m. when they received a call for a disturbance at a home on McBride in Dupo.
That's when police found 46-year-old Darryl Mantz dead at the home.
Someone, that according to Sgt. Clossen, Allen had a relationship with.
"They knew each other. They had worked together. It is still undetermined upon our investigation what the motive was," he said.
A Dupo police officer was the first to arrive on the scene and officers said Allen then shot the officer in the shoulder.
Dupo Chief of Police, Dennis Plew, said the support for the officer and their department has been incredible.
"The people that showed up at that hospital just to see the family. The newly appointed Chief of Police of Saint Louis showed up at the hospital. We don't know him. I don't know him personally. I don't even believe he's from this area. That just speaks a lot about the respect that we have for one another and what a huge family and love we have for one another," he said.
Police said after shooting the officer, Allen then stole the officer's car and drove it to his home on McBridge, which lead to the standoff.
Officers then found Allen dead in his garage from self-inflicted gunshot wounds with an AR-15 rifle next to him.
"Which we know was used in the self-inflicted gunshot wound to himself and to the homicide. It's still being investigated, but we're pretty sure, that was the same weapon also used when he shot the Dupo police officer," he said.
One big question still for police is how Allen that gun.
Since, according to St. Clair County court records, Allen has been charged with dozens of felony and misdemeanor cases from 1999 till now.
Court records show that Allen has everything from battery-related offenses to drug charges to armed violence and unlawful possession of a weapon by a felon.
Allen was even charged with reckless homicide after a 2009 incident outside City Nights in East St. Louis, where he was working as a bouncer.
Records show he was sentenced to a year in prison after he ran over Anthony Rice.
5 On Your Side spoke with Rice's family back in 2009, where they told us they believed his death was intentional and racially motivated.
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