EVANSDALE, Iowa (AP) — A sheriff investigating the apparent kidnapping and slaying of two Iowa cousins said Friday that the discovery of the young girls' bodies is a long-awaited break in the case that could help find their killer.

Black Hawk County Sheriff Tony Thompson said investigators would be deliberate in pursuing the case of Lyric Cook and Elizabeth Collins, who were 10 and 8 when they disappeared in Evansdale in July. Hunters stumbled upon two bodies believed to be Cook and Collins in a wooded wildlife area some 25 miles away on Wednesday.

Thompson said it could take "several weeks" for their autopsies to be complete and the results to be made public.

"We're going to be extremely meticulous and we're not going to apologize for that," he said a phone interview with The Associated Press. "We've got an opportunity to find a killer."

After nearly five months of chasing tips and theories about the girls' whereabouts, Thompson said police "finally have something credible. We finally have something we can sink our teeth into" in the high-profile case.

Thompson's remarks indicate the case is becoming a homicide investigation. At a news conference Thursday, Thompson's chief deputy said the investigation was leaning that way but that police would wait for the autopsy results before making the change.

Teams of local and federal officers have scoured the Seven Bridges Wildlife Area in Bremer County for evidence since the discovery of the bodies, searching in ditches along the road, fields and woods. The Iowa Medical Examiner's Office, which is handling the autopsies, was also at the scene. That office has declined comment on the autopsies.

The sheriff's office had asked neighboring counties, including Bremer County, to search their parks and wildlife areas for the girls after they vanished last summer, Thompson said. He said that as far as he knows, Bremer County officers did search the popular hunting and fishing spot but that the bodies would have been hard for anyone to spot.

"Even the hunters, if they had gone five feet in either direction, would not have found those bodies," he said.

The girls left the Collins' home in Evansdale, where they were being watched by their grandmother, for a bike ride July 13 and never returned. Authorities found their bikes and a purse near a recreational lake in the city, and their disappearance sparked a massive search and kidnapping investigation involving the FBI, state and local police.

The cousins' families had been hoping they would come home, maybe even for Christmas, until this week's news.

"This 100 percent blindsided us and it absolutely did them as well," said Sara Curl, a friend of the girls' families. Continued...