NAMPA, Idaho (KTVB) -- Nampa police say two Nampa children who were reportedly kidnapped by their father have been found safe in Washington state, about an hour north of Portland, Oregon.

Their dad, Joshua Reavis, is in custody. On Twitter, Nampa police thanked Washington State Police for their help. Earlier today, an AMBER Alert was issued for the children, 3-year-old Slevin Reavis and 2-year-old Estaleyn Reavis.

KTVB spoke to Brittni Reavis, the mother of the two kids, shortly after she learned their were safe. She expressed relief and said she can't wait to hug them. She was working with a travel coordinator to try and figure out how to get up to Washington, where her children were with Child Protective Services. Although Joshua Reavis, 31, is a custodial parent, police expressed concern for the children's safety because of Reavis' mental state and statements he made to the children's mother before taking them. The children had been missing since Monday.

They were last seen at Reavis' home on East Dewey Street in Nampa. The children were believed to be in "imminent danger," police spokesman Sgt. Joe Ramirez said. Idaho State Police issued an AMBER Alert, which was quickly expanded to western Montana, Oregon and Washington.