Another man approached the stage to yell at Buttigieg and South Bend Police Chief Scott Ruszkowski, ignoring the moderator's attempts to restore order.
Buttigieg returned to campaigning Friday with a trip to Miami but skipped a SC event attended by 21 other presidential candidates to fly home for a Friday evening community march.
"That's just being reactive, it's not being proactive and making sure this never happened and having rules in place for South Bend police officers and body cameras", Coffman said.
Buttigieg kept his emotions in check, something that has become a trademark of the candidate on the campaign trail but did let out a mix of frustration at being interrupted and visible sadness at the fact that these issues plague the city he has led for eight years. "It's my job to face it".
At least one person was killed in the melee at Kelly's Pub, South Bend police tweeted.
Buttigieg says he'll send a letter to the federal Department of Justice's civil rights division and notify the local prosecutor that he'd like an independent investigator appointed.
Buttigieg, 37, remained calm throughout the town hall meeting even as he struggled to make himself heard, shouted down by mainly black protesters, some of whom shouted "liar!" as he sought to explain how he will deal with the shooting investigation, and as he promised transparency.
Buttigieg said this was the beginning of a conversation and that he would work with the community to increase trust.
The mayor has had a rocky relationship with some of the city's black residents, stemming in part from his decision to fire the African American police chief early in his mayoral tenure, and replace him with two consecutive white police chiefs.
The town hall grew contentious when some community members questioned whether the mayor had done enough to reform the police department in the city of 100,000 people, which is about a quarter black. Events in South Bend are threatening to significantly undermine what had been a relatively trouble-free campaign.