DUPO, Ill. – The accused gunman who was in a standoff with law enforcement on Sunday just outside a southern Illinois town had a lengthy criminal history, dotted with dozens of felony and misdemeanor cases.

Around 10 p.m. Sunday, police found the body of Reginald Allen inside the garage of his home in the 700 block of McBride Avenue. Allen, 40, had died of a self-inflicted gunshot wound.

Police claim Allen shot and killed one person and wounded a Dupo, Illinois, police officer earlier that day.

According to Master Sgt. Brad Clossen, St. Clair County Sheriff’s Department, things began just after 1:15 p.m. on McBride and Stolle Road. Deputies were notified of a shooting and found an adult man dead in the front yard of a home.

Allen is believed to have fled the scene of the shooting in a piece of construction equipment belonging to his family. A Dupo officer spotted Allen a short time later and went to confront him. Clossen said Allen shot the officer in the neck and shoulder, and used the officer’s patrol vehicle to drive himself home.

Allen barricaded himself inside his home, Clossen said. For the next several hours, police from multiple jurisdictions, including the Illinois State Police, closed off traffic to the street. Late Sunday evening, a SWAT team eventually made its way into the home and found Allen dead.

Police have not disclosed a motive for the shooting, but Clossen said Allen and the deceased shooting victim knew one another. The victim’s name has not been released.

Meanwhile, the injured officer underwent surgery and is expected to recover, Clossen said.

A check of St. Clair County court records shows Allen as the defendant in 32 felony cases and 29 misdemeanor cases from November 1999 until present day.

Records show nearly 20 battery-related offenses, four incidents of unlawful possession of a weapon, multiple drug charges, and four counts of armed violence.

Allen faced a reckless homicide charge for running over and killing a man during a fracas outside an East St. Louis nightclub in 2009.

In that incident, Allen was accused of driving over Anthony Rice in the parking lot of City Nights. Prosecutors said Allen yelled racist insults at Rice and his brother before throwing a rock at their vehicle. One of Rice’s friends pulled out a pistol and fired shots into the air in response, at which point Allen got into his truck and ran down Rice.

Rice was 23.

Charges were not filed in court until June 2011. Allen eventually pleaded guilty to a lesser charge in December 2015, and was sentenced to one year in state prison. Allen had faced up to six years in prison.