Young men were drinking vodka and beer and smashing bottles at in West Somerville Saturday night, according to a police report.
Police arrested five people at the field, and one man fled from police, possibly carrying a weapon, leading Somerville and Arlington police to search unsuccessfully for the man, the report says.
Police responded to Dilboy at about 10 p.m., when the park closes.
When they arrived, police saw two teenagers sitting on a bench with an open container of vodka, and a third man standing nearby who backed away when he saw the officers, according to the report.
Police saw the man put a shiny object into his waistband, which they thought might have been a firearm or weapon, the report says.
He ran, and police arrested the two teenagers, a 17-year-old and a 15-year-old, before pursuing him.
He ran toward two men, Edwin Grossett, 28, of Dorchester, and Wilfredo Velasquez, 31, of 103 Gilman St., who were drinking cans of Becks, according to the report.
Police arrested Grossett and Velasquez, and at that point another young man, Francisco Aponte, 19, of 153 Alewife Brook Parkway, walked into the middle of the scene and said, "That's my brother you're arresting," the report says.
When police told him to leave, he refused, said "Get outta my face I ain't leaving," and then struggled with police, who arrested him, too, according to the report.
Officers then teamed up with Arlington police to search for the man who ran away, but they couldn't find him or any weapon he may have discarded, the report says.
Grossett, Velasquez and the two teenagers were charged with trespassing and violating open container ordinances. Aponte was charged with disorderly conduct, resisting arrest and trespassing.
Please remember that allegations contained in police reports do not indicate a conviction.