The first hint of trouble was captured by surveillance cameras: Four males entering Northeast High School at 9:30 p.m. Sunday. At 4:30 a.m. yesterday, the school building engineer found a trail of what appeared to be sawdust leading from his office down the hallway.

That's when he spotted the first chickens.

"I turned on the light, and out of the corner of my eye, I saw 12 chickens in a circle," Michael Cice said. "Big, huge chickens.

"I looked down the other end of the hallway and I saw more chickens. There were chickens everywhere."

In the basement. On the first floor. On the second floor, too. There were 85 of them - Rhode Island Red hens, to be precise. And they made a mess.

School officials were left no choice but to cancel school for 3,600 students. Crews spent the day and part of last night cleaning and scrubbing the school on Cottman Avenue with a solution of water and bleach.

Now the search is on for the culprits.

Fernando Gallard, a district spokesman, said they probably were students.

"It's usually your first sort of assumption, that this is a school prank done by students," Gallard said.

"We don't know where the chickens came from or who they belong to," he said. "I'm pretty sure there is a very upset poultry farmer somewhere who wants them back."

Poultry pranks are not unheard of. In June, officials at Moorestown High School threatened to move graduation indoors after a weeklong spate of pranks that included chickens and crickets loosed in the hallways.

Cice said there was evidence to suggest the chicken shenanigans at Northeast were also a senior prank. He said the number 167 - the number of Northeast's 2008 graduating class - had been marked on all the lockers.

So, will the chickens come home to roost for the four intruders?

Police are studying the video to try to identify the culprits. Students were expected to return to school today if the city Health Department gives its OK.

As for the chickens, they were "safely transported" to Fox Chase Farm in Philadelphia, where they are being cared for by the staff of Swenson Arts and Technology High School, which operates vocational programs in agricultural industries and environmental science.

Experts say the best way to catch chickens is to turn out the light so they think it's night and begin to roost. Unfortunately, Cice said, that tip did not reach Northeast until he and the other custodians had chased the chickens into bathrooms on each floor.

"They weren't too fast," Cice said. "We just caught them and corralled them into the bathrooms."

Until yesterday, he said, the closest he had gotten to a chicken was "Col. Sanders'."

He said officers from pest control put the chickens into poultry cages for transport to Fox Chase.

Although the farm has a small poultry program, David Kipphut, principal at Swenson, said the Rhode Island Reds would be quarantined until their health could be assessed.

Chris Ryder, a spokesman for the Pennsylvania Department of Agriculture, said a veterinarian was scheduled to inspect the birds.

"They seem very healthy, and some of them are laying eggs," Kipphut said. "We are feeding and watering them.

He hoped the hens would "be returned to their rightful owner." If not, Kipphut said, he hopes they will be adopted. The cost of each chicken is $4, but they are "priceless to a farmer," he said.

For students and staff, the experience was also priceless.

"They were so cute," said Joy Deltoro, a secretary in the college counseling office who saw the birds in two wire crates before they were taken away.

"You had everybody laughing," she said of the reaction among other staffers. Deltoro said it was wrong to release the chickens at the school, but added, "It's better than hearing about a shooting."

Corina Oxford, 16, and her sister Destiny, 14, arrived at the school around 7:30 a.m. yesterday to find a longer-than-normal line of students trying to get in.

They were directed to the auditorium, where they waited for at least an hour before being excused for the day.

They then spent a half-hour in the freezing cold, waiting for their mother to pick them up.

Nevertheless, they were both happy about the chickens.

"It got us out of school," Destiny said.

District officials also were trying to determine why the building's alarm system was not activated when the intruders entered.

"That's still under investigation," Gallard said.

He called it "an expensive prank. There's the lost staff hours, the police hours, and the cost of cleanup."

He predicted that whoever was apprehended would have to pay a hefty fine.

"It's not going to be chicken scratch," he said.

Contact staff writer Martha Woodall at 215-854-2789 or martha.woodall@phillynews.com

Inquirer staff writer Robert Moran contributed to this article.