The father of a man who has been arrested in the wake of a deadly mass shooting in Highland Park, Illinois reportedly ran for mayor of the city in 2019 and was defeated by a pro-gun control Democrat.

Robert E. Crimo III was apprehended by police following a manhunt on Monday but has not yet been charged with any crime. He had been named as a "person of interest" following the shooting that left six people dead and dozens more injured.

Crimo's father, Bob Crimo Jr., ran for mayor of Highland Park in 2019 and was defeated by incumbent Mayor Nancy Rotering, according to a number of media reports at the time and since Crimo III was arrested.

This undated handout photo provided by the City of Highland Park Police Department shows Robert (Bobby) E. Crimo III. Highland Park Police Chief Lou Jogmen said Monday, July 4, 2022, that police have identified 22-year-old Crimo as a person of interest in an Independence Day parade shooting in suburban Chicago.City of Highland Park Police Department

The elder Crimo is a small business owner in the city of around 30,000 people and unsuccessfully challenged Rotering, a Democrat with a long history of supporting gun control measures.

He owns Bob's Pantry & Deli in Highland Park and both he and Crimo III were named in a 2018 obituary for Robert Crimo Sr., the grandfather of the arrested man, which is still available online.

The Chicago Tribune reported on Crimo Jr.'s mayoral campaign in May 2019, while Patch later reported that Rotering had defeated Crimo Jr. in the race by a margin of more than 2-to-1, securing a third term.

On his website, which is no longer accessible, Crimo Jr. reportedly said: "We need to take a hard look at Highland Park's many ordinances, rules, and regulations, and see if we can improve them or change them in order to stimulate new business growth within our downtown business district."

Rotering has long been an advocate for gun control and The Daily Beast reported on Monday that she had signed an ordinance in 2013 banning assault weapons in Highland Park.

"The City Council has determined that assault weapons are traditionally not used for self-defense in the city of Highland Park, and that such weapons pose an undue risk to public safety," the ordinance said.

A pro-gun group and a local gun collector attempted to challenge the ordinance in 2015 but the U.S. Supreme Court refused to hear the appeal and it is still in place.

Many details about the shootings on Monday have not yet been made available, but Rotering told NBC's Today that the gun used was "legally obtained."

"I think, at some point, this nation needs to have a conversation about these weekly events involving the murder of dozens of people with legally obtained guns. If that's what our laws stand for, we need to reexamine the laws," Rotering said.

Illinois Governor J.B. Pritzker, who is also a Democrat, made a similar point in his remarks reacting to the shooting.

"There are going to be people who say that today is not the day, that now is not the time to talk about guns," Pritzker said.

"I'm telling you, there is no better day and no better time than right here and right now. It's the Fourth of July, a day for reflection on our freedoms. Our founders carried muskets, not assault weapons. And I don't think a single one of them would have said that you have a constitutional right to an assault weapon with a high-capacity magazine."

Police crime tape is seen around the area where children's bicycles and baby strollers stand near the scene of the Fourth of July parade shooting in Highland Park, Illinois on July 4, 2022.Getty