In November, two crime alerts were sent out to the University of Massachusetts student body informing them of separate reports of armed robberies that had taken place 12 days apart. In both cases, one at the Puffton Village and the other at Brandywine Apartments, a gun was alleged to have been shown during the encounter.

Those two incidents are part of a larger surge in armed robberies in Amherst, which has seen six armed robberies reported since Nov. 6 through Dec. 21. In addition to the armed robberies students were notified of in the November crime alerts, two armed robberies were reported at the Boulders and Southpoint Apartments each.

“Armed robberies are not common in Amherst and having the amount that we’ve seen in the past two months is much higher than we’ve seen in the past,” said Jennifer Gundersen, captain of administration at the Amherst Police Department.

Before Nov. 6, only one armed robbery in Amherst had been reported in 2015, Gundersen said.

The armed robbery reported at Brandywine Apartments was different in nature from the other ones reported, which she said were similar.

“That was a home invasion, where we think they entered that particular apartment for a reason,” Gundersen said.

“The other five that occurred were all outside,” she added.

Each of the armed robbery cases were described as an ongoing investigation by Gundersen, who said that a 17-year-old Amherst man was arrested at one of the scenes. She added that two additional men have been charged and are awaiting arraignment.

“We do anticipate additional criminal charges on some of the other cases,” she said.

On Dec. 15, Terrell Phok, a 19-year-old Amherst resident, was arrested following a month-long investigation into the armed robbery of a pizza delivery man on Dec. 3.

Gundersen said the Amherst Police Department is looking at whether the reported armed robberies are connected and that the APD does not currently have enough information to determine whether there is a possible social explanation for the increase in armed robberies.

Gundersen said that Amherst residents should always be aware of their surroundings and that individuals in south Amherst, where four of the armed robberies were reported, should be especially vigilant.

Gundersen compared the sudden increase in armed robberies in Amherst to burglaries, which she said occurred cyclically. Gundersen said that two to six burglaries could often occur in a short period of time, followed by long stretches where none are reported.

“They do tend to cluster,” she said.

Stuart Foster can be reached at [email protected] or followed on Twitter @Stuart_C_Foster.