Police made two arrests in connection with allegations of voter fraud in a Hamilton riding but didn’t lay charges, according to a police affidavit filed on Tuesday to keep the documents related to the case sealed from the public.

Media organizations, including CTV News, have applied to unseal court documents related to allegations of voter fraud and ballot-stuffing at a Progressive Conservative riding association nomination meeting in May 2017.

Police started an investigation into the allegations after receiving a complaint from one of the losing candidates in the ridings of Hamilton West-Ancaster Dundas.

In an affidavit filed by the lead detective in the case, Det. Const. Adam Jefferess, argued that releasing the contents of the court documents “would compromise the integrity of this investigation.”

According to the affidavit, two homes were searched by officers in connection with the investigation. Multiple documents, digital devices and storage media were seized.

Some of the devices were sent to a third-party forensic examiner in the United States due to “a claim of solicitor-client privilege.” Police have not yet been able to review the contents of those devices.

The location of the homes searched was not released.

“The investigation is very much ongoing and is extensive in size,” Jefferess wrote in the affidavit. “I know of no other time that a Canadian police service has conducted a criminal investigation into allegations of fraud at a nomination meeting conducted by a political party.”

Officers seized about 61 items, including a group of 1,800 PC party ballots and about 1,648 pages of emails. Authorities have also identified almost 150 witnesses in connection with the investigation.

“A number of witnesses have been uncooperative with police and have refused to provide statements, or have attempted to control the interview, which has hampered the investigation,” Jefferess wrote.

In the affidavit, Jefferess argued that unsealing the documents “could lead to the destruction of evidence by other possible suspects.” He also said that keeping the documents sealed helps investigators check the authenticity of incoming tips or witness statements.

The media has argued in an application to unseal the documents that there is a “great public interest as the investigation involves issues going to the heart of a crucial part of the democratic process in Canada.” Lawyers representing media have also noted that keeping the materials sealed violates the public’s right to know, the open court principle and is a violation of the Canadian Charter of Rights and Freedoms.

Ontario Premier Doug Ford commented on the investigation at a news conference on Wednesday, saying that it was not his role to interfere in a police investigation.

“I was elected to as Leader of the PC Party to clean up Patrick Brown's mess. And let's make no mistake about it, he left a real mess,” Ford said. “ Moving forward, the police are going to deal with it properly. I have all the confidence in the Hamilton Chief — that they are going to do the right thing. But it's not my job as premier to interfere in any police investigation.”