Father Who Killed His Two Children In Pennant Hills Found Dead

His body was found this morning.

Father Who Killed His Two Children In Pennant Hills Found Dead AAP Photo

A man being sought after a teenage girl and boy were killed in a suspected domestic violence-related shooting at a home in Sydney's northwest has been found dead.

The suspect's body was found early on Friday morning, Nine Network reported.

NSW Police declined to comment.

The 15-year-old boy and a 13-year-old girl were found shot dead in their bedrooms at a house in Hull Road at West Pennant Hills shortly before 5.30pm on Thursday.

Their mother, 36, arrived shortly after police and was treated by paramedics for severe shock.

Det Supt McFadden said it was a "targeted attack".

"We do believe that it may well be domestic violence-related and our focus at the moment is on the investigation to locate our person of interest," he told reporters late on Thursday.

It's believed the person being sought was the father of the children, aged in his 50s.

NSW Ambulance Inspector Kevin Sweeney said paramedics were faced with an "extremely distressing and stressful situation".

Police inquiries continue and an extensive forensic examination led by the homicide squad is underway.

It's unclear how many shots were fired but detectives are speaking with several witnesses to determine what happened.

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