Washington shooting
Police officers take cover behind vehicles lining the road during a standoff at a rural property near Belfair, Washington, February 26, 2016 in this handout photo provided by Mason County Sheriff's Office in Shelton, Washington. REUTERS/Mason County Sheriff's Office/Handout

A little girl is the sole survivor of a crazed gunman who killed four people before committing suicide in front of shocked police officers in Washington State. The man is thought to be the father of some of the victims and the surviving girl is also said to be related to the family.

A Washington State SWAT team and other officers had been negotiating with the man for three-and-a-half hours at an address in Belfair before he turned the gun on himself. According to local media the man had called a police officer he had spoken to before on Friday to say he had shot and killed his two children and a woman, thought to be his wife, and another person.

The officers have not revealed the identities of the dead and police have not said whether those found slain were indeed who he had said he had murdered. The girl has been taken for evaluation at a local hospital after the incident on 27 February.

Mason County Chief Deputy Ryan Spurling said according to AFP: "The individual shot four people, including children, and then after a standoff shot himself."

Spurling said the victims were found in one of about 11 outlying buildings on the property in the town, which is situated around 60 miles west of Seattle. A neighbour had said that the couple had been married for four to five years.

It is thought that the woman had two teenage sons who were adopted from Russia during a previous marriage and a daughter who was adopted from China. The man was said to have had a heating and air conditioning business.

On Thursday three people were killed and 14 injured, five critically, when a gunman opened fire at multiple sites, including his workplace near Witchita, Kansas. The gunman, identified as an employee of lawn-equipment company Excel Industries, was shot dead in a gun battle with police.