It started as a downtown party entitled The Blarney Blowout.
Police were prepared for that crowd, but students took things in a different direction.
It was a calm scene Friday afternoon at the Town House Apartments north of the UMass campus. The area was very quiet and not many people were hanging around outside.
Contrast that with the images from this past Saturday. Police estimate that 2,000 students packed into the complex, causing a very dangerous situation.
"Students were being injured with bottles and cans being thrown in the crowd," said Capt. Jennifer Gundersen. "[There were] drunken patrons that the ambulance crew needed to move."
In order to gain control of the situation, Amherst police called in seven off-duty officers, which doubled the size of the crew already on duty. It was a necessary but costly move for the department.
"Immediately we see the overtime expenditures from the previous two weeks to the next two weeks triple," stated Gundersen. "We forecast what we can spend on a weekly and monthly basis."
"We were stressed," said Chief Tim Nelson of the Amherst Fire Department. "We were right on the edge."
The fire department had its own issues to deal with. They were pushed to the limit with five ambulances operating at one time.
Nelson's main worry was not being able to help someone in need, suffering from something like a heart attack, due to treating injured or drunk students.
UMass is not taking the situation lightly.
Six of its students were arrested during the party. The school cannot get into specifics, but told CBS 3 that any student violating the university code could be subject to suspension or expulsion.
Officials said they did not endorse the idea or party itself. They strive to create events with a much safer environment.
"We have worked closely with the town and will continue to do so," said UMass spokesman Edward Blaguszewski. "We have worked to create events on campus that are closely monitored by our student affairs office and campus police."
Amherst police said all the groups involved need to work together if they want to see improvement.
"There are a lot of people at the table," said Gundersen. "A lot of people are invested in coming up with ideas to see this activity decrease."
This past weekend involved more than just Amherst authorities.
In order to break up the crowd, police said they were joined by three UMass officers and nine Massachusetts State Police officers.
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