(CNN) A retired police captain fatally shot during looting in St. Louis was passionate about helping young people and would have forgiven those behind the violence on the city's streets, his son says.
David Dorn, 77, was killed while responding to an alarm at a pawnshop overnight Monday, St. Louis Police Department announced in a news conference Tuesday.
"Throughout the night, we made 25 arrests for various charges. And then there were 55 businesses and counting that were burglarized and had property damage," St. Louis Police Chief John Hayden told reporters.
"One of those businesses had one of our retired captains, retired captain David Dorn, who retired after 38 years. During the looting process, David Dorn was exercising law enforcement that he learned here."
Chief Hayden said Dorn had been "a fine captain" who had been very well-liked and looked up to by many of the department's younger officers.
CNN affiliate KTVI reported that Dorn had been killed around 2:30 a.m. Tuesday, dying on the sidewalk in front of the pawn store he had been providing security for.
St. Louis Regional Crimestoppers is offering a reward of up to $10,000.00 for any information that leads to the arrest of the person or persons responsible.
Dorn's son Brian Powell told the station that Dorn had been a father of five and had 10 grandchildren.
Dorn had been passionate about helping young people, Powell said, and he believed his father would have forgiven those behind the violence and tried to talk to them.
"Because he was real big on trying to talk to youth. And mentoring young people as well. He tried to get them on the straight and narrow and everything," Powell told KTVI.
"The person who pulled the trigger, my message to them would just simply be, just step back from what you're doing. Know the real reason that you're protesting. Let's do it in a positive manner. We don't have to go out and loot and do all the other things," Powell said.
Powell's reflections were echoed in a tweet by the Ethical Society of Police, which read, "(Dorn) was murdered by looters at a pawnshop. He was the type of brother that would've given his life to save them if he had to. Violence is not the answer, whether it's a citizen or officer. RIP Captain!"
President Donald Trump also paid tribute to Dorn on Twitter, saying, "Our highest respect to the family of David Dorn, a Great Police Captain from St. Louis, who was viciously shot and killed by despicable looters last night. We honor our police officers, perhaps more than ever before. Thank you!"
Trump's tweet was not universally welcomed. Filmmaker Ava DuVernay tweeted in response: "We won't let you use this Black man for your political gain. You can try. But we will not let it happen. May he rest in peace. May the truth about his murderers come to light. And may he not have his name dragged into your vicious, evil games. "
Dorn had retired from the St. Louis City Police Department in 2007, KTVI reported, and later became police chief at Moline Acres. Retired St. Louis City Police officer David Ellison told the station that Dorn had helped him out of poverty and into a life as a police officer.
"Dave Dorn was a great man. He was fair -- the sharpest, cleanest guy," he said.
Powell said that his father couldn't stay retired after he left the city force. "Police work ran through his veins."