The DFL caucus in Ward 6 Precinct 3 has a unique distinction among Minneapolis’ 119 gatherings Tuesday night: It’s the only one shut down by the authorities.The caucus at the Brian Coyle Center in Cedar-Riverside produced an overflow crowd of more than 300, a pre-caucus argument handled by the police and a subsequent physical attack on one of the participants.Eventually, staff from the Coyle center decided to shut down the event, and police quickly dispersed the crowd.Emotions had been running high more than an hour before the scheduled 7 p.m. start and escalated even more by caucus time in the Cedar-Riverside Somali stronghold.The cause of the uproar was the strong feelings among backers of longtime Rep. Phyllis Kahn and her challenger, Minneapolis School Board Member Mohamud Noor, who has strong support in the Somali community.A large number of Noor supporters had congregated at the community building more than an hour early. Shortly after, an argument over procedures broke out between the Kahn and Noor supporters.Staff at the center called in the police, and it looked like the argument had died down, but tensions lingered after the authorities left the room.The Kahn campaign remained concerned that Noor supporters from outside the precinct – and even the city — would show up to support his bid. Their concerns proved accurate in at least one case, when four Noor supporters from Brooklyn Park were turned away.The crush of people, at least 300, raised fire concerns, caused huge lines to get into the caucus and forced party staff to hold back attendees from clogging the registration area……Ilhan Omar, a staffer for Minneapolis Council Member Andrew Johnson and vice chair of the Senate district, was attacked by a group of about five people.Then a Noor supporter launched herself into the fray and was eventually shoved into a police officer’s grasp.Police dragged the woman out of the building and handcuffed her, but eventually let her free. Omar escaped without serious injuries.