AMHERST — Hundreds of people gathered in the back yard at a North Pleasant Street fraternity house, where loud music was playing and some underage guests were found urinating on a neighboring property, led to enforcement actions by Amherst Police late last Friday night.

Officers responded to Alpha Sigma Phi fraternity, 374 North Pleasant Street, at 11:09 p.m., finding a section of the property fenced off with tarps and noise being generated by a live DJ. The fraternity had registered the party and received a courtesy call earlier in the evening to quiet down, which didn’t happen.

Three men were arrested on charges of violating the town’s noise and nuisance house bylaws, police said. Each of those violations of the bylaw could lead to $300 fines.

In addition, a person being a minor in possession of alcohol was summoned to court, while a heavily intoxicated woman at the location was transported by Amherst Fire Department ambulance to Cooley Dickinson Hospital in Northampton.

About 15 minutes before responding to the fraternity, three college-age teenagers, who had been at the party, were found urinating against the side of a North Pleasant Street building.

They were arrested for being minors in possession of alcohol, police said. Two more people urinating against the same building were warned and sent on their way,

At 11:58 p.m., police took an associated complaint from a nearby resident concerned that drunken college-age people were coming up to her door and ringing the doorbell. Officers found more than a dozen people on her property. They were sent on their way.

During the 216 calls for service over the weekend, police also responded to College Street, where around 12:42 a.m. Saturday two registered parties were breaking up. That caused congestion along the road when numerous ride-hailing drivers arrived to pick people up. At 12:52 a.m. a 20-year-old Amherst man urinating in public outside a nearby business was summoned to court on a charge of disorderly conduct.

At 1:43 a.m., police issued a nuisance house ticket to one of the College Street homes, finding the lawn covered in beer cans and trash.

Meanwhile, at Crestview Apartments, tenants had a small party Saturday at 11:58 p.m. that got publicized on Yik Yak, which led to hundreds of people showing up. The residents and a property management company called police to remove those party-goers who hadn’t been invited.

Police also took a report at 1:14 a.m. Sunday from a woman who said she was intentionally elbowed while getting pizza at a downtown restaurant. Police said they didn’t find any evidence an assault took place.