Two young men were walking near Errington St. in Chelmsford Saturday when four men exited a car and approached the pair, demanding money.
Police say an altercation ensued where one of the victims was struck in the leg with a mallet. The four men stole money from their victims and sped away in the car.
As a result of a police investigation, a 17 and 18-year-old were arreted and charged with robbery. The two will appear in Sudbury court Monday.
Police are currently seeking arrest warrants on the other two suspects, an 18 and 19-year-old, both from Chelmsford.
Anyone with information is asked to call Crime Stoppers at 675-TIPS.