Boston police and a SWAT team were called to a Dorchester neighborhood Friday evening after an unstable man locked himself in a Wrentham Street house that he shares with his parents. Superintendent William Gross said the police action was taken as a precautionary measure and ended without any injuries. Family members called police after the 27-year-old man “lashed out” at his father, an off-duty Boston police officer, and was unable to be restrained, Gross said. Police negotiators persuaded the man to leave the house voluntarily after about an hour, police said. The man was taken to Beth Israel Deaconess Medical Center and has not been charged.Nicholas Jacques can be reached at email@example.com.