The father of a missing 10-month-old Missouri girl said Thursday he discovered an open window and unlocked door when he returned home to find his daughter missing from her crib.

Jeremy Irwin told Fox News that he immediately knew something was wrong when he came home from work at 4 a.m. Tuesday and discovered an open window, an unlocked front door and lights turned on.

"Most of the lights in the house were on, which was really weird," Irwin said.

FBI search dogs have scoured the Kansas City home where Lisa Irwin was last seen in her crib. Law officers canvassed nearby woods, walking shoulder-to-shoulder looking for clues. Jeremy Irwin and his fiancee, Deborah Bradley, have tearfully begged for the person who took their daughter to leave her somewhere, anywhere, safe.

"We just want to get her back home as quickly as we can," Irwin told Fox News.

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    Relatives say the parents of the girl have given police several names as they try to think of potential suspects or people who paid especially close attention to the child.

    Her mother's cousin said Thursday that they family is "scraping for anything" as they try to think of anyone who recently looked at the child strangely.

    About 300 law officers have used helicopters, all-terrain vehicles and door-to-door interviews to look for the baby since she disappeared sometime late Monday or early Tuesday.

    Jeremy Irwin and Deborah Bradley had been cooperative with police since reporting her missing. But they changed course Thursday, Kansas City police spokesman Steve Young said.

    "Tonight, they decided to stop talking to detectives, and I don't have to illustrate how that affects the investigation. That speaks for itself," he said.

    Police weren't releasing details about their plans for Thursday, if they would keep the investigation close or expand the search. Capt. Steve Young said police would be working overnight and early Thursday "same as before."

    "We're going to keep working as long as calls come in and we think there's absolutely anything we can do," Young said late Wednesday.

    The child's parents are not suspects and spoke to the media for the first time Wednesday, pleading for their daughter's safe return and asking the public to call police with any information.

    Clutching a purple stuffed Barney doll that presumably belonged to her daughter, Deborah Bradley tearfully added: "We just want our baby back."

    Young said investigators have no new leads and no named suspects.

    "With that being said, everything is still on the table," Young said shortly after the news conference. "If we had more to go on, we could start eliminating some things, but we frankly don't have anything to justify elimination."

    The child was last seen around 10:30 p.m. Monday when her mother checked on her in her crib. Her father discovered the baby missing about five hours later, when he got home from a late-night shift at work.

    The Irwins also said their cell phones were stolen, but that nothing else appeared to be missing from their home.

    Police have said one possibility they were investigating was whether someone entered the home through a front window and snatched the baby, but they haven't pointed to any sign of forced entry.

    St. Joseph police obtained surveillance video from a highway truck stop north of Kansas City after someone reported seeing a "suspicious" car with a couple traveling with a baby who may have resembled Lisa Irwin, Cmdr. Jim Connors said Wednesday.

    Connors said Kansas City police have been notified and would be given the video, but acknowledged that the report was "probably one of many."

    "Everyone's looking for a cute little baby," he said.

    Lisa has blue eyes and blond hair, is 30 inches long and weighs around 28 pounds. She was last seen wearing purple shorts and a purple shirt with pictures of white kittens.

    FBI agents clad in white plastic suits used search dogs earlier Wednesday as they went into the family's light-green ranch-style home in a cozy neighborhood along a winding street. An FBI spokeswoman declined to discuss details of the investigation.

    Young said the suits were to hide the FBI agents' scent from the dogs so they could get original scents of the girl. He also said investigators interviewed the girl's parents until about 10:30 p.m. Tuesday, but did not take them into custody.

    "Everything we've thought of doing we've probably done two or three times," he said. "Over 300 law enforcement officers have been involved. They've walked a wooded area three times in shoulder-to-shoulder searches, taken dogs in three times -- different dogs each time -- and none of those led us anywhere."

    The National Center for Missing and Exploited Children was doing all it could to assist. Center president Ernie Allen was cautiously hopeful that Lisa would be found, saying that of the 278 infant abductions nationwide over the past 28 years, only 12 of those children didn't come home safely.

    An Amber Alert was issued Tuesday morning but called off after 12 hours. Police said it was a formality because the alerts are designed to raise awareness early in an investigation.

    Click for more on the disappearance of Lisa Irwin from Fox4KC.com

    The Associated Press contributed to this report.