Looks like the "Blarney Blowout" lived up to its name.

Four police officers were slightly injured and more than 70 people were reported arrested on Saturday after a pre-St. Patrick's Day celebration in Amherst, Mass. The "Blarney Blowout" turned into, well, a blowout.

The air was filled with snowballs and flying beer cans as mobs of college-age partiers descended on apartment complexes near the University of Massachusetts' flagship campus in Amherst.

In a Saturday statement, the university took pains to denounce the "unsanctioned" Blarney Blowout, which school officials warned could result in suspension or expulsion from the university.

Pictures and video from social media show youths standing on top of cars and pouring beer on other partiers from balconies as skirls of a bagpipe and chants of "U-S-A!" fill the air. One video shows a young man apparently trying to yank down a light pole.

Riot police from the Amherst Police Department, the University of Massachusetts Police and the Massachusetts State Police tried to stamp out the fun, chasing the party from one apartment complex to the next throughout the day.

Officers were pelted with debris of varying peril as they tried to budge the crowds, with one officer getting a cut on his hand when a glass bottle shattered, police said. 

At the Pi Kappa Alpha Fraternity House, police were hit by "glass bottles, full beer cans, rocks and snowballs" thrown from the roof, porch and windows of the house, according an account of the party posted to the Amherst Police Department's blog. Police vehicles were also scratched and dented in the action. The post said officers had to pepper-spray the crowds.

The department's post began with a fulmination on the dangerousness of previous Blarney Blowouts.

"The size and scope of these gatherings has led to many safety and quality of life issues, including violence and fights, injuries, severe alcohol intoxication, sexual assaults, excessive noise, property damage, and violence towards the police and community members," the department said.

Police said this year's arrests were expected to result in charges of assault with a dangerous weapon, assaulting police officers, breaking and entering, failure to disperse and inciting a riot, among others. By 7:30 p.m. Saturday there had been 43 arrests; as of Sunday, the Associated Press reported that police had made 30 additional arrests.

Those arrested were also expected to fall under the scrutiny of university officials, who said they'd taken several steps to warn off partygoers before this year's Blarney Blowout.

"In the days leading up to the gathering, the university reached out to students, landlords, parents, faculty and staff in a campaign to communicate the importance of students acting safely and respecting the property of others," the university said in a statement.

It added that letters also had been sent "to students who had been disciplined for alcohol-related misconduct in the past year and to students who live in off-campus housing cited for noise or nuisance complaints reminding them of the possible consequences of bad behavior."

And yet the party went on.

It was "perhaps one of the worst scenes we have ever had with drunkenness and unruliness," Amherst police Capt. Jennifer Gunndersen told the Republican of Springfield, Mass. "It is extremely upsetting. It is very dangerous."

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