Charges will not be filed against a Prince William County police officer who fatally shot a 15-year-old during a call Friday, prosecutors announced Monday.

The teen, whom police identified Tuesday as Ruben Urbina, was shot as officers were responding to a report of a hostage situation at a home in Haymarket.

"It's always tragic when a young person loses his life," said Prince William County Commonwealth's Attorney Paul Ebert. "But there comes a time when police have to do what police have to do, and this was one of those occasions."

The ruling dismayed Urbina's family, who said in an interview Monday that they felt the shooting was not justified.

Ebert said the situation began when the teen called 911 to say he had a bomb strapped to his body, was holding his mother hostage and had a knife. Ebert also said the teen indicated he didn't mind being shot by officers.

Ebert said the teen had attempted suicide the night before and was suffering from a mental disturbance. Urbina's brother, ­Oscar, 18, said Urbina had previously been in treatment for a mental condition, which he declined to specify, but he had been doing well recently.

When officers arrived at the teen's home in the 6800 block of Hartzell Hill Lane around 10:45 a.m. Friday, Ebert said the teen struck his brother's girlfriend with a three-foot-long crowbar and then moved aggressively toward officers. The officers commanded the teen to drop the crowbar, but he did not comply, Ebert said.

When the teen was less than 10 feet away, an officer fired twice. Police said in a news release Monday that Urbina had raised the crowbar over his head in a threatening manner before he was shot.

The teen was struck in the upper body, Ebert said. Police said the officers rendered aid, but the teen was later pronounced dead at the scene.

The woman who was struck with the crowbar was transferred to the hospital for treatment and is expected to recover. No officers were injured.

When asked if he thought less lethal force could be used, Ebert answered: "I don't think so."

Ebert said officers later found a knife at the scene. He also said the encounter was challenging because the teen was wearing a coat, so it was difficult to see if he had concealed a weapon or indeed had a bomb. Police said no bomb was found and determined there was no hostage situation.

On Tuesday, police identified the officer who shot Urbina as Robert Choyce, 35, a seven-year veteran of the force. Choyce is a member of the department's tactical team and has not been involved in any other on-duty shootings.

Authorities said the officer was not wearing a body camera.

Oscar Urbina said the family was distraught about Urbina's killing and that police had not given a full account of what actually happened. He declined to detail what information hadn't been reported by authorities, saying the family wanted to consult with an attorney first.

"There's a lot of stuff that prosecutors don't know or want to hide," Oscar Urbina said. "They are trying to make the shooting look justified."

Oscar Urbina said his brother was a sophomore at Pace West, a special education school in Gainesville. He said he was funny, enjoyed computer games and liked to go on long walks.

Prince William County Police Chief Barry M. Barnard said the situation was difficult for the family and the officer involved.

"This whole event is a tragedy for the family," Barnard said. "At the same time, it's a traumatic event for an officer. No officer comes to work wanting to use force."