Update: 3 Additional arrests made in MBTA Shawmut Station attack

Four juveniles have been detained in connection with a violent attack and robbery outside an MBTA station earlier this week.

Transit Police Supt. Richard Sullivan said two men, ages 69 and 47, were surrounded by a group of teenagers while they were at the bicycle rack that is just outside Shawmut Station.

The victims told Transit Police a group of teenage boys pulled out a knife and demanded money around noon Monday. When the 69-year-old and 47-year-old men said no, the boys punched them several times, leaving them bloodied, according to witnesses.

Sullivan said both men were treated by Boston Emergency Medical Services personnel outside Shawmut Station and did not need to be taken to a hospital.

Transit police said a 15-year-old was taken into custody on Wednesday and three additional juvenile males were placed into custody on Friday.

This investigation is still ongoing.

This is a developing story. Check back for updates as more information becomes available.

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