Striking Air Canada ground workers in Toronto and Montreal returned to work Friday after the company was granted an injunction by an arbitrator ordering an end to the labour dispute that disrupted flights across the country.

At least 60 flights were cancelled or delayed by Air Canada Friday in Toronto and another 30 in Montreal, according to the company's website. The flights were destined for Canadian and U.S. cities.

The wildcat strike began after three workers were suspended for heckling federal Labour Minister Lisa Raitt as she walked through Toronto's Pearson International Airport Thursday night, union spokesman Bill Trbovich said Friday.

When other workers heard of the suspensions they walked off the job and 37 of them were fired on the spot, he said. Baggage handlers joined the strikers in Montreal Friday morning.

He said the union didn't sanction or support the strike, which had also spread to Vancouver and Quebec City.

"We told them that if you go on strike it's illegal and you could lose your job if you continue to do this," Trbovich said.

The arbitrator reinstated the fired employees in a decision Friday and said there would be no repercussions against the striking workers.

Some of the unionized workers then began to return to work, but a handful remained at Pearson's Terminal One chanting "shame on Lisa Raitt."

Air Canada said it's waiving its rebooking fee for passengers stranded by flight cancellations and delays caused by the strike.

It's also advising passengers to check their flight status online before arriving at the airport.

The wildcat strike should have been expected, former CAW president and labour relations expert Buzz Hargrove told CTV News Channel Friday.

"We've watched the federal government and provincial governments slowly erode the rights of workers to join a union, which they fought long and hard to get under legislation," he said in a telephone interview from Naples, Fla.

Continued government interference in both private and public sector labour negotiations was the root cause of the walkout at Air Canada, Hargrove said.

"The frustration level of people who fought long and hard for the right of free collective bargaining and the right to strike is showing in this dispute," he said.

Had Ottawa allowed the collective agreement process to take its natural course, there wouldn't be a problem, Hargrove said, suggesting pressure of a lockout or strike deadline actually speeds up the bargaining process.

If there was to be a strike at an airline such as Air Canada, the union would be required to give 72 hours notice, allowing travellers to make alternate arrangements, he said.

Minister of Transport Denis Lebel said in a statement Friday he was pleased the company and union reached an agreement to end the strike.

"These actions have adverse effects on the Canadian economy, and cause significant problems for Canadians and tourists who are travelling throughout the country," he said.

Earlier Friday, Raitt said the walkout was "an illegal strike action that is disrupting travel for Canadians."

She said in the email that "law enforcement agencies have been contracted, and will be deployed if necessary."

The federal government has intervened in several Air Canada labour disputes, recently banning the company and its pilots and mechanics unions from disrupting service over bitter contract talks.

Ottawa also had to intervene in contract disputes involving the airline's flight attendants and its customer service agents.

Raitt defended the legislation, saying it was done in the interest of the national economy.

Earlier Thursday, many passengers said they had no idea where their luggage was, or how they were going to get to their destinations. One passenger described the situation at the airport as "a zoo."

By Friday morning, a line up of hundreds of people snaked through the departures area as passengers tried to rebook their flights.

Passenger Cecil Stein flew in from Newfoundland, but his connecting flight to his final destination in South Carolina was cancelled by the time he landed in Toronto.

"We just get a run-around," said Stein. "There's no one, really, here to help you."

Stein walked over to a bank of phones that some passengers were directed towards to rebook their flights.

Those who were lucky enough to get an operator on the line said it took nearly an hour to get through.

Others got only a busy signal.

Some passengers were told to go back home and re-book their flight from there.

Aaron Huizing was heading back to his home in Ottawa from Punta Cana in the Dominican Republic when the walkout began.

Huizing, who was travelling with a group of 30 people, said he never should have booked a vacation with the airline.

"I say the same thing every time. ‘I'm never going to deal with Air Canada again.' Maybe next time I'll listen to myself," he said.

Earlier Thursday, angry Air Canada workers rallied in front of Prime Minister Stephen Harper's constituency office in Calgary to send him what they called a symbolic message.

With files from Emily Senger and The Canadian Press.