Prince William County police said yesterday that seven people, including two juveniles, were arrested during a family reunion at a Dale City home Saturday night after an officer responding to a noise complaint fatally shot a Maryland man.

Jose Leonides-Marquez, 31, a construction worker from Silver Spring, died after a county officer fired one round from his service weapon, police said. The officer fired after he was attacked by Leonides-Marquez and other relatives who grabbed his gun belt and tried to choke him at the home in the 13300 block of Orangewood Drive, they said.

Relatives yesterday disputed the police account, saying a fight broke out after one of the officers struck another man, Fredy Armando Guerra, 41, with a baton. They said Leonides-Marquez was trying to pull Guerra away from the officer when he was shot.

"All he was trying to do was help the cop," said the victim's 16-year-old nephew, who has been charged with obstruction of justice and released to his family. "He pulls Fredy out and pulls him away from the cop, and once he does that the cop goes boom. Everybody was surprised, and the cop stood still for a moment and did nothing. He knew he made a mistake."

Prince William Police Chief Charlie T. Dean declined to comment on the family's version because he said the shooting is under investigation, as is routine.

According to a statement, police said that when two officers arrived at the home, they were "suddenly attacked" and that one officer was pinned in a corner of the porch where a "violent" group of people grabbed his gun belt, struck him on the head and choked him. Leonides-Marquez was "the primary aggressor," the statement said.

A 14-year-old high school freshman from Hyattsville was charged with felony assault and battery on a police officer and disorderly conduct, and remains held without bond at the Prince William juvenile detention center. Milagro J. Guerra, 40, of the 2900 block of Powder Mill Road in Hyattsvillewas charged with disorderly conduct and resisting arrest, and was released on $1,500 bond.

Others charged with felony assault and battery on a police officer were Fredy Guerra, also of the Powder Mill Road address, three counts; Carlos Ernesto Marquez, 36, of the Dale City address, two counts; and Jorge H. Hernandez, 38, of no fixed address, and Francisco Miguel-Perez, 27, of no fixed address in Silver Spring, one count each.