Orion Krause, the 22-year-old man accused of killing four people in Groton on Friday, appeared in Ayer District Court Monday morning to face four counts of murder.

While authorities have not identified the four victims, friends of the family said Krause's mother and grandparents were killed. The fourth victim was a caretaker for the elderly couple.

Authorities called the deaths a "situation of tragic family violence." Krause went to a neighbor's home after the killings and said he just murdered four people.

Krause graduated recently from Oberlin College in Ohio and was known for his music, according to friends.

A vigil for the four victims was held in Groton on Sunday. Local Rev. Elea Kemler asked people to pray for the family and for Krause. She said something must have gone seriously wrong for Krause to commit such acts.

A weapon was recovered from the scene. Investigators believe all four victims, three women and one man, were beaten to death.