A man is charged with criminally negligent homicide after police say he opened fire in Brooklyn, killing his sister and wounding her daughter.

William Thurmond, 70, is also charged with weapons possession and assault.

Officials say the victims were arguing with Thurmond when he took out a gun and started firing just before 10 a.m. Tuesday in a basement on 25th Street near Avenue D in Flatbush.

63-year-old Carol Lovell was killed, and her 37-year-old daughter was taken to the hospital with graze wounds.

"He is a very quiet person, always just making sure in front of the house look clean and so on," said one neighbor.

No motive has been released.