A 20-year-old Somerville man pleaded guilty to participating in a violent, unprovoked attack on a jogger in Medford.
Niall Vallega pleaded guilty in Middlesex Superior Court and was sentenced to a total of five years in prison followed by five years of probation, the Middlesex district attorney's office announced on Thursday.
Vallega and a group of others drove by the victim and yelled threats as he was on Salem Street in Medford in March 2011. Moments after, he was approached by a group of men and threatened. The victim tried to walk away, but that's when the group, apparently unprovoked, attacked the man.
Authorities said Vallega punched the man in the eye and attacked him with other members of the group. The man was also hit over the head with a glass bottle and stabbed in his side by another person.
Police were able to identify the suspects based on a GPS location device worn by one of the group members, cell phone records and witness statements.
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