But in a statement, Chief Wade Carpenter said Immigration and Customs Enforcement (ICE) informed him that four people were detained between 5 a.m. and 8 a.m., according to the Park Record newspaper.
The four people were sought on felony counts involving re-entering the country or other unspecified offenses, according to the report.
The operation came one week after ICE officials detained 680 immigrants in five cities across the country, who, most likely, will be deported.
Neither city officials nor members of Park City's immigrant community have much information regarding Friday's detentions.
But Park City resident Ernest Oriente said accounts shared on social media and in conversations indicate the operation appeared to go on much longer and suggested there could be more than four detainees. The dearth of information is leaving people wondering, he said.
"The official account makes it sound like they just came and took four people between 5 a.m. and 8 a.m.," Oriente said. "But that's not the real story. It's far from what happened. The community is frightened."
Rebeca Gonzalez, program director for Bright Futures Program at Park City High School that serves minority students, said young people are asking whether they should go to school and whether their parents could be taken away.
"It's causing a lot of fear in students," she said. "They ask, 'Why is this happening. What can we do?'"
President Donald Trump has said he will deport 3 million undocumented immigrants but only the "bad ones."
ICE is not conducting sweeps that target undocumented residents indiscriminately, said ICE spokeswoman Rose Richeson.
"Our deportation officers conduct targeted enforcement operations every day in locations around the country as part of the agency's ongoing efforts to protect the nation, uphold public safety and protect the integrity of our immigration laws and border controls," she said. "These operations involve existing, established Fugitive Operations Teams."
Such official statements from ICE have done little to assuage fears, said Beth Armstrong, executive director of The People's Health Clinic in Park City, which provides care to the uninsured. People began calling the clinic Friday in a state of panic, she said.
In January, community leaders and local law enforcement officials met with immigrants at St. Mary's Catholic Church, Armstrong said, to explain to them that they didn't have to live in fear.
"Now that is exactly what has happened," she said. "They deserve, at least, to be told what to expect."
The clinic is not a sanctuary, Armstrong said, but will point immigrants to resources that can assist them.