The DFL Party chair apologized for the melee that erupted Saturday at a Minneapolis City Council candidate convention, saying video evidence and witness statements make it clear that supporters of one council challenger were to blame.

No one was arrested but police officers called to the scene heard reports of fights and injuries; a man in his 30s was taken to HCMC for treatment of a medical condition, and a woman in her 40s was treated by EMS at the scene for a minor injury, a police spokesman said.

"It is clear that the conflict was instigated by supporters of city council candidate Nasri Warsame," read a statement from DFL Party Chairman Ken Martin. "Harassment and violence are unacceptable, and we expect candidates and their campaign teams to work hard to curb such behavior when it comes from their supporters, staffers, or volunteers."

Martin said on Twitter that he plans to call an emergency meeting of the party's leadership and will propose banning from the DFL anyone found responsible for the violence on Saturday.

Warsame didn't respond immediately Sunday to an email seeking comment.

The convention, held at the Ella Baker Global Studies & Humanities Magnet School in the Uptown neighborhood, ended in a frantic scene and with no candidate endorsement.

Video posted to Twitter by John Edwards, who blogs about Minneapolis politics as Wedge Live, shows the chaos break out at the Ward 10 endorsing convention after supporters of Minneapolis Council Member Aisha Chughtai took the stage. Warsame supporters shouted and jeered in the gymnasium, and a man waving a Warsame sign jumped on the stage. More people in Warsame shirts followed and continued to shout, slam on tables and wave signs, disrupting the convention proceedings.

"This is embarrassing!" convention chair Sam Doten shouted, finally adjourning after pleading futilely for order. "We are shutting this down!" he said. "This is no longer safe!"

In a Facebook post afterward, Warsame said his campaign manager "has been assaulted by one of the other campaign staff members, and he's now being transported to hospital by an ambulance."

"The convention was shut down due to turmoil, and all the people were instructed to exit the building," Warsame wrote. "No endorsement at this point, but more questions to ask regarding the process."

Chughtai also released a statement, casting blame on Warsame's campaign for leading his delegates onto the stage and "assaulting me and my supporters as I was about to begin my convention speech." Chughtai said more than a dozen of her supporters were "physically assaulted," along with a photographer documenting the convention, and more were bullied and harassed as "an attempt to scare us."

"Eventually, our supporters locked themselves in our hospitality room, so they would be safe and away from a rapidly escalating and dangerous situation," she said. "The Warsame campaign followed us off the floor and was only held back by a group of brave volunteers who blocked a hallway while our supporters were able to escape from the locked hospitality room out a back door of the building to safety."

Minneapolis DFL Chair Briana Rose Lee said on Twitter that "several DFL volunteers were assaulted" at the convention, including members of the state executive committee.

"The behavior displayed today was despicable and unacceptable," Lee wrote. "I don't know the next steps yet. But there will be repercussions."

The video does not show clearly what preceded the fight. "I don't know what triggered it," Edwards said in an interview. "People just kind of spontaneously came forward to the stage."

Edwards said there had been votes on rules and disagreements on procedure, and that issues with language translation appeared to be causing some confusion earlier in the day. Chughtai was about to give the first speech of the convention, and Warsame would have been next, followed by a question-and-answer segment and then votes.

A woman who attended the convention with plans to vote for Nasri said the event was poorly run. Marjorie Simon, a convention delegate from precinct 1, said Warsame supporters were frustrated by poor interpretation for non-English speakers and a feeling that the convention was being run with a bias toward Chughtai.

It was when Chughtai's supporters walked onto the stage with her that Warsame supporter's frustrations boiled over.

"It was as if it was a foregone conclusion for them that they had won already," she said of Chughtai's supporters.

Doten agreed the mood shifted when Chughtai was about to address the convention. Some Warsame supporters in the visitors' section loudly booed and then encouraged others to come forward. Doten said he saw Warsame looking on as his supporters stormed the stage. When Warsame did come up on the stage, Doten handed him the microphone but Warsame was unable to calm his supporters.

"I found it very alarming behavior from someone who wants to be an elected official," Doten said.

Correction: Previous versions of this article misstated when candidates' supporters typically take the stage at DFL nominating conventions.