TAMPA, Fla. (AP) — Authorities in several states on Thursday searched for two young boys believed to have been kidnapped by their father from their maternal grandparents' Florida home after their grandmother was tied up.During a news conference, an FBI agent and a colonel with the Hillsborough County Sheriff's office said tips about 4-year-old Cole Hakken and 2-year-old Chase Hakken have poured in from several states.Authorities say the boys' father, 35-year-old Joshua Michael Hakken, entered his mother-in-law's house north of Tampa, tied her up and fled with the children. They said the children could be in a black 2006 GMC pickup owned by their father."It's the manner in which the kids were taken that concerns law enforcement," FBI Special Agent Dave Couvertier said.Officials say Hakken and the children's mother, 34-year-old Sharyn Patricia Hakken, are the prime suspects in the abduction. An earlier news release said "both suspects are anti-government and have attempted a previous abduction at gun point in Louisiana," but Couvertier said officials are focused on the kids and not the parents' political views."We're working on the safe return of the entire family, specifically the children," he said.