Updated

A Seattle man fatally shot his adult daughter and teenage granddaughter before turning the gun on himself late Monday, police said.

KCPQ reported that the shooting took place in a south Seattle home shortly after 8 p.m. local time. Police said they received a call for help from a 10-year-old boy, who told them his grandfather had waved a handgun at the two victims before shooting them. The boy said his grandfather then turned the gun on himself.

None of the victims were identified, but authorities said the gunman was in his 60s.

The boy who reported the shooting was unharmed, but "shaken up," Assistant Police Chief Nick Metz told reporters at the scene. The child was placed in the care of his extended family. There did not appear to be any other people in the house, Metz said.

Police said the motive for the shooting wasn't immediately known. Medics pronounced all three people dead at the scene.

Seattle Mayor Ed Murray said the shooting appeared to be "a family tragedy," before adding that there was no danger to the surrounding neighborhood.

The Associated Press contributed to this report. 

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