AMHERST — All students living in the 22-story Coolidge Hall in the Southwest Area of the University of Massachusetts campus were safely evacuated for three hours Sunday night into early Monday morning after an unattended candle caused a small fire in a dormitory room on the 20th floor, according to the Amherst Fire Department.

The incident was one of several in town throughout the Labor Day weekend that kept both firefighters and police officers busy, with students at UMass and the area’s colleges returning for the fall semester.

For police, two significant incidents occurred, one at a downtown restaurant Friday night in which underage people overcrowded the space and may have been served alcohol; the other at a downtown shop Saturday morning, when a man accused of punching and seriously injuring a person there allegedly attempted to steal a vehicle and hit an officer before being arrested.

The Fire Department’s response to Coolidge Hall occurred at 11:08 p.m. on Sunday, when a fire alarm in the building was activated and some living in the building called 911 to report the sprinkler system had been activated due to smoke.

Every occupant was required to leave the high rise, with fire crews encountering moderate smoke on the 20th floor and discovering the fire had already been extinguished by the sprinklers. The fire, which consumed some items on a desk, was started by a candle left burning.

The sprinklers caused some water damage on the 20th floor and floors below.

About three hours after the response, most of those living in the building returned to their rooms, but those whose rooms are on the upper four floors waited an additional two hours, or until 4 a.m., when the sprinkler system was restored. Those living in the room where the fire began were not able to return immediately.

There were no injuries to residents or firefighters.

Previously, on Friday at 9:58 p.m., police officers responded to Amherst Burger Co., 104 North Pleasant St., for possible underage drinking inside, with more than 75 college-age people present on the front patio and sidewalk at the business. A manager was advised by officers to maintain control of the business. He told officers, though, that some employees hadn’t shown up for work.

One person leaving the business with alcohol was identified as possessing a fake ID.

Two more underage people were found at Gabe’s Underground, 41 Boltwood Walk, early Sunday morning. They were issued citations for the offense. Checks at other bars and restaurants found everyone in compliance.

Another significant incident occurred Saturday at 7:49 a.m. when a 30-year-old man from Albany, New York allegedly punched and started assaulting people unknown to him at a shop, apparently unprovoked. He then allegedly attempted to steal a vehicle, leading to brief foot pursuit by police near the Bangs Community Center, where he became combative. He was arrested on charges of assault and battery to cause serious bodily injury, assault and battery on a police officer, resisting arrest, disorderly conduct and attempted larceny, police said.

Over the course of the weekend, police issued four additional citations to underage people found in possession of alcoholic beverages while on public ways. An additional nine individuals were warned about possession of open containers of alcohol while on public ways, and one person was issued a warning for being underage and in possession of alcohol.

Police also responded to numerous noise complaints throughout the weekend, but the only significant incident happened at 7:38 p.m Sunday, when a $300 ticket for violating the town’s noise bylaw was issued to a North Attleboro resident at a Sunset Court home. The residents living there had a live band performing, with loudspeakers set up in the yard, for about 50 college-age spectators.

Police also issued warnings for violating the town’s noise bylaw to residents of Puffton Village, South Pleasant Street, Kellogg Avenue, Strong Street, Chestnut Street, Townehouse Apartments, Gray Street, State Street and Nutting Avenue.

Scott Merzbach can be reached at smerzbach@gazettenet.com.