Authorities used helicopters, boats, a bloodhound and a house-by-house search Thursday to try to find three boys missing since the prior evening.

Their families' search for the boys, ages 5 to 11, began soon after the three friends vanished around 5 p.m. Wednesday as they played outside one of their homes. Police said they were notified at about 9 p.m.

Authorities have no reason to believe the boys were abducted, but that possibility had not been ruled out, said police Lt. Mike Lynch.

As time wore on during a day of worries, tearful embraces, prayers and frantic searching, relatives fretted about how the oldest of the boys — who has limited mental abilities and attention deficit disorder — might fare without his medication.

"We've done everything we can. The only thing we can do now is hope and pray we'll turn around and they'll be walking down the sidewalk and saying, 'We're here,'" said Jennifer Calo, an aunt of 11-year-old Anibal Cruz (search).

Elba Cruz, Anibal's mother, said she was outside with the boys Wednesday and went in for just a few minutes to check on something cooking in her kitchen.

When she returned, her son, 6-year-old neighbor Daniel Agosto (search) and 5-year-old friend Jesstin Pagan (search) were missing.

Jesstin Pagan and his mother, Jessica, were visiting the Cruz home from their house in nearby Mount Ephraim.

"I turned my back for two seconds and they were gone," Jessica Pagan said.

Daniel's mother was inside her home across the street napping at the time. "This is the first time for him to leave the block," she said Thursday as she watched police cordon off a nearby wooded area with yellow tape.

In the mostly Puerto Rican Cramer Hill neighborhood, which is considered a relatively safe place in a city one crime analyst called America's most dangerous, family and neighbors immediately began a search.

When police arrived, they used helicopters and began going door to door. Search efforts lasted through the night, then intensified Thursday morning with authorities giving special scrutiny to abandoned homes, railroad tracks and parks.

Relatives of the boys said that they were spotted Wednesday evening at a nearby water-ice stand, then a pizzeria, but Lynch said those sightings could not be confirmed.

Police said that because of the boys' ages — and Anibal's mental capabilities — they did not believe they could have gotten too far from the neighborhood. Still, police in neighboring Pennsauken and Mount Ephraim searched in their towns.

A police dog tracked a scent taken from one of the boys' clothing to an overgrown wooded area along the Delaware River a half-dozen blocks from the Cruz home.

Throughout the day Thursday, a state police helicopter buzzed over the woods while three fire department rescue boats patrolled the river's bank.

Meanwhile, weary volunteers handed out fliers to people in passing cars while police considered all the possibilities.

"There's no tangible evidence we've received to say, 'Yeah, there's foul play here,"' Lynch said. At the same time, he said, authorities approached the disappearances as a possible crime.

He said investigators were determining whether any registered sex offenders lived in the neighborhood and looking into whether anything in the boys' homes would indicate a relative wanted to abduct them.

Lynch said that neither avenue was bearing fruit.

Neighbors in the closely knit area kept a close watch on police. As a search dog followed a scent, she was followed through streets of single-family homes by several police officers, a small pack of reporters and photographers and a group of residents, including a girl on a bike and a mother pushing a stroller.