The union that represents personnel from U.S. Immigration and Customs Enforcement (ICE) is asking Oregon state and federal officials to conduct a criminal investigation of Portland Mayor Ted Wheeler over his handling of the 38-day Occupy ICE protests in the city this summer.

The National ICE Council sent letters to state Attorney General Ellen Rosenblum and U.S. Attorney General Jeff Sessions, asking them to look into whether Wheeler committed misconduct when he directed police officers to not respond to certain calls for service during the protest in front of the local ICE field office, the Oregonian reported.

“We believe that Mr. Wheeler has committed the crime of official misconduct,” stated an Oct. 3 letter sent by Sean Riddell, a Portland-based attorney representing the union. “Our attempts to compel Mr. Wheeler to take reasonable action, correct and/or cease his criminal activity have been unsuccessful.”

The union also said Wheeler should temporarily give up his duties as police commissioner.

"If a rank-and-file police officer was presented with an ongoing crime for 30 days and did not take appropriate action that officer would be placed on administrative leave and subject to an internal investigation," the letter continued.

Nearly 60 police calls were associated with the protests, which began June 17. In total, 16 police reports were written.

The letter states the crowd around the Portland ICE office grew after June 20, when Wheeler said he didn’t want the Portland Police Bureau to get “sucked into a conflict” with a federal agency he didn’t agree with.

Wheeler has said he detests the actions of ICE agents separating some children from their parents facing deportation, according to the Portland Tribune. In a statement, he said he did nothing wrong and argued that his approach was necessary to protect the protesters’ First Amendment rights to free speech.

"Make no mistake. They are coming after me because I am a vocal opponent of the [Trump] administration's policy of separating kids from their parents," Wheeler said in a statement. "Previous claims made by Sean Riddell have fallen apart upon further inspection and these claims, if investigated, will too."

The protests came on the heels of the agency’s crackdown on undocumented immigrants, with some calling for ICE to be abolished.

At the time, Wheeler said he preferred to have federal authorities enforce laws on federal property rather than city police.

During the weeks-long gathering, reporters said they were assaulted or threatened, food cart employees reported being threatened and ICE employees reported racist insults. Some activists were heard chanting “No racist police” and some reffered to officers as “Nazis.”

When it concluded in July, the area was littered with books, makeshift toys, liquor bottles, tents and furniture.

Riddell said Wheeler directed police to not respond to comes police calls "to advance his own personal political agenda, advance his politcal career and punish citizens he perceived to hold alternative politcal beliefs."

In the letters, he cited public statements made by Wheeler and messages sent to an aide and the police bureau, ordering officers to respond to the protests only in the case of an immediate threat to lives or safety.