Belhassen Trabelsi, one of the richest and most powerful members of the former Tunisian regime who's been fighting deportation from Canada, has disappeared off the radar of Canadian authorities.

After years of fighting his deportation, the brother-in-law of former Tunisian dictator Zine el Abidine Ben Ali was supposed to be put on a plane and sent back to Tunisia by the Canada Border Services Agency on Tuesday.

But documents from a Federal Court decision last week show that Trabelsi has disappeared.

He failed to show up for a scheduled meeting with CBSA officials on May 24, and Trabelsi's own lawyer told Judge Yvan Roy that he couldn't reach Trabelsi and has no idea where the man is.

The disappearance puts into question Canada's efforts to deport a man accused of stealing possibly billions of dollars from the Tunisian people.

A U.S. diplomatic cable leaked in 2010 said Trabelsi's holdings included "an airline, several hotels, one of Tunisia's two private radio stations, car assembly plants and a real estate development company."

Close connection to Montreal

Trabelsi has always had a close connection to Montreal.

After travelling to the city several times on government business in the 1990s, he applied for and was granted permanent residency status.

Following the fall of the Tunisian regime in 2011, Trabelsi and his family fled to Canada and have been living quietly in Montreal ever since.

The Canadian government has since revoked Trabelsi's residency status and frozen his assets.

In a bid to have some of the restrictions on his assets loosened in 2014, Trabelsi told a court he needed money for a private security detail, chauffeur service and to pay to have his children educated at an English-language private school in Montreal.

A fight to stay in Canada

Trabelsi is wanted on fraud charges in Tunisia.

Since 2011, he has applied for refugee status in Canada, and his claim was denied. He then argued that if he was returned to Tunisia, he wouldn't receive adequate medical care. This argument was also rejected by the courts.

Canada Border Services Agency had arranged to finally send Trabelsi back to Tunisia on Tuesday.

He was fighting that in court and had applied for a stay of removal order, but Roy rejected that as well.

In his decision from last Thursday, Roy revealed Trabelsi had disappeared.

"In the opinion of Mr. Trabelsi's own lawyer, he cannot be found. This lawyer has submitted an affidavit declaring that his client is unreachable," Roy wrote.

What happens next is up in the air.

Regarding what steps the federal government might take next in the case, Public Security Minister Ralph Goodale said he couldn't comment "on the procedure involved."

"It's CBSA's responsibility to deal with those who are in the country without the proper authorization, and they are seeking to discharge their obligations," he said.

The Canada Border Services Agency could not immediately be reached for comment.