He is also expected to face a charge of assault and battery with a dangerous weapon, 15 counts of improperly storing a large-capacity firearm near a minor and one count of receiving an untraceable firearm. Hanafin was arrested in Vermont later on the day his mother’s body was found and was extradited to Massachusetts. It was not clear whether he had an attorney who could comment on the allegations.

Andria Hanafin was found dead at the family’s Center Avenue home early last Thursday. Her husband, Ryan Hanafin’s father, told investigators that he and his son had recently argued over Andria’s regular fostering of cats, according to an account in court documents. The dispute has not been established as a motive for the killing.

Authorities recovered 84 cats from the home. The animals are being cared for at MSPCA-Angell shelters; the organization said some need medical attention and that the large influx is straining its resources.

More than 100 people gathered Wednesday to remember Andria Hanafin. Middlesex County District Attorney Marian Ryan attended and spoke about the impact a violent death can have on a community, including children and first responders. “These are the kinds of things that frighten people,” she said, adding that the trauma can be underestimated even when responding to such events is part of someone’s job.

The charges are allegations, and Hanafin is presumed innocent unless proven guilty in court.