AVON, Ind. Federal immigration authorities made 20 arrests during a traffic blitz in Indiana on Tuesday, sources told local affiliate WXIN.

Those sources said Immigration and Customs Enforcement worked with local police in Avon, Indiana, to conduct several dozen traffic stops throughout the town to detain illegal immigrants.

There are no police reports from Avon police documenting the arrests, and they do not appear in the Hendricks County Jail public log.

The FBI confirmed they were part of the operation.

“We did not conduct traffic stops as the FBI is not authorized to conduct those,” a spokesperson said in a statement. “We were there to assist Avon Police and ICE/ERO with any needed federal warrants.”

After numerous attempts to obtain information, Avon Police Chief Sean Stoops sent WXIN a lengthy email that framed the operation differently.

He confirmed his officers conducted a “traffic blitz” in the Avon area and made numerous stops for reasons such as traffic violations, registration violations and aggressive driving.

“During a few of these traffic stops, our police officers encountered undocumented and/or unlicensed foreign nationals,” Stoops wrote. “Avon Police officers requested assistance from Immigration and Customs Enforcement agents. Agents responded to the traffic stop location and assisted with identifying the foreign nationals and conducted their own investigation into the status of those individuals.”

However, sources told WXIN that ICE reached out to Avon police first. The agency also contacted other police departments, who declined to participate.

In his statement, Stoops said it works with all federal law enforcement agencies and that if they requested their help, his officers would assist.

Lisa Koop with the National Immigrant Justice Center said ICE uses local law enforcement agencies to circumvent the normal judicial process. Koop said agents are required to have probable cause to make a warrantless arrest.

“If they are seeking to circumvent those requirements and bypass the need to establish that they’ve gotten the administrative warrant or that they’ve established that they’ve probable caused to make an arrest, then a convenient shortcut would be to lean on local police,” Koop explained. “[They can] make what may or may not be a legitimate traffic stop and if they have someone in criminal legal custody…it makes it a whole lot easier for ICE to come in and apprehend someone and initiate deportation proceedings.”

Koop argued the legality of that strategy remains an open question. She said she believes police still need a legitimate reason to stop someone.

“If police are only pulling over people who look like they might be immigrants in their view, then yes, it’s racial profiling,” Koop said. “Whether there’s probable cause to make any kind of arrest, criminal or immigration related, I think is called into question.”

WXIN went back to Stoops with various questions about the relationship between Avon Police and ICE and how those traffic stops were conducted.

“There are some portions of our strategic operational planning that we do not share publicly to ensure the safety of our officers and to protect them in the future and to ensure mission success,” Stoops said. “As I stated in my previous email, we reciprocate with all federal, state, and local law enforcement agencies when it comes to assisting with law enforcement operations and actions.”

WXIN has reached out to ICE for comment on the sweep, but has yet to hear back.