At 8 a.m. Sunday the population of Kinsman, Ill., stood at 109. An hour later it nearly doubled, as upwards of 100 federal agents and police swooped in on the tiny, rural community. And no one seems to know why.

The law enforcement officers, including FBI agents, immigration officials and state police, surrounded an Islamic meat plant in Kinsman, cordoning off the area and briefly detaining the plant's handful of employees.

The FBI isn't saying much, and the county sheriff is mum too, leaving Kinsman's residents mystified. The bust, in a town that has no local police force, involved dozens of vehicles, a pair of snipers and a helicopter flying overhead, witnesses said — but it ended without even a single arrest.

"We're all baffled," Mayor Mark Harlow said. "You know, stuff like this doesn't happen in a small community."

The unusual show of force has residents spooked and has left the mayor searching for answers.

"The public reaction is ... are they safe? We don't know," Harlow said. "What are they doing? We don't know. Are they making bombs? We don't know."

Harlow said residents of the town rarely see the five or six employees of the First World Management butcher shop, which provides ritually slaughtered and processed lamb and goat meat for Muslims living in Chicago, 50 miles to the northeast.

Some of the workers were handcuffed during the raid, but they were eventually released, Harlow said. He said the workers are foreign-born and live in a trailer on the property behind the plant's meat locker, and they have never harmed anyone in town.

"I've never seen them do anything out of the ordinary," he told Foxnews.com. The workers' residency status is unknown.

Kinsman is a sleepy town carved out of a patchwork landscape of farms in the heart of the Grain Belt. Its few square blocks are home to a post office, church and bar, and there isn't a restaurant or gas station in sight.

But the two men listed as the proprietors of the business appear to be under scrutiny. A staff member at the First World Management office in Chicago identified Syed Hamid, 51, as an employee, and confirmed that Tahawara Hussain Rana, 48, is the owner of the business.

Residents believe Hamid lives in a house adjoining the shop in Kinsman and runs the slaughterhouse. Hamid, a doctor, has been in talks with a Chicago lawyer, George Jackson III, who told Foxnews.com he doesn't anticipate Hamid will be charged with a crime. Jackson said he and Hamid had spoken to investigators since the raid.

Rana's case isn't so clear. Jackson said he could not comment, and phone calls to the Rana household in Chicago went unanswered.

Law enforcement officials declined to comment on whether the massive raid was connected to a series of high-profile arrests orchestrated by the FBI in recent weeks that focused on terror suspects.

"No one is in custody, no charges have been filed," said Cynthia Yates, a spokeswoman for the FBI's Chicago office. "There's not much to say."

The sheriff of Grundy County, Ill., where Kinsman is located, said he was informed of the impending raid about two weeks ago, but his officers did not play a tactical role.

"The only thing I can tell you is that it's an ongoing criminal investigation, and basically everything that's being done is through the FBI," Sheriff Terry Marketti said.

Though Immigration and Customs Enforcement officials were present at the raid, it's unclear what role they were playing. The Department of Homeland Security has recently refocused its efforts on employers who hire illegal immigrants, rather than on the immigrants themselves.

And unlike the targets of similar sweeps that were the norm in the Bush administration, the Kinsman shop employed only a handful of workers, a fraction of the size of other plants that have drawn the attention of ICE officials. Also, unlike in past immigration raids, no workers were brought into custody.

"It was crazy," said Grundy County Board Chairman Francis Halpin, who lives in nearby Morris, Ill. "I never thought I'd see anything like this in Kinsman."