In the end, seven people were arrested, but not before officers used smoke grenades, tear gas and foam bullets to disperse the crowd of several hundred people that gathered along Seventh Street between 13th and 14th avenues.
Several students who were at the off-campus block party said Sunday that it was partly a spillover from the university's annual "Spring Jam" event, which was planned by the student activities office and ended Saturday night.
But other students said the large gathering had more to do with the two keg parties at houses along Seventh Street.
Sophomore Abe Gross, who lives a block away, said one party was underway as early 8:30 a.m. and had already spilled into the street. By 5 p.m., the street was nearly impassible for motorists because of "rowdy students drinking beer and yelling," he said.
Officers who arrived about 8 p.m. after a report of a large party were greeted with flying beer bottles, rocks and other debris, Garcia said.
"At one point, someone threw a 12-pack of beer at an officer," he said. "There was a lot of defiance there."
The initial responding officers were forced to retreat and call for backup. In the meantime, Garcia said, the crowd swelled to an estimated 400 partygoers who "only got more incorrigible" by lighting a large bonfire, jumping on cars and trying to tip one over on its side.
"They were creating mayhem in the neighborhood," Garcia said.
About an hour and a half later, more than 50 officers —- wearing helmets and gas masks and carrying battalions — tried to quell the crowd with smoke grenades and chemical irritants. The foam bullets were used to "identify the main agitators"