A South African firefighting agency has apologized to Canada and promised an investigation after a pay dispute led to a strike by 300 firefighters who are battling the blaze near Fort McMurray.

But the agency isn’t yet ready to comment on allegations by Alberta Premier Rachel Notley that it violated Alberta’s labour law by paying below the minimum wage.

The agency, Working on Fire, is paying a daily allowance of $15 to the 300 South African firefighters who arrived in Alberta last month, plus a further $35 for each day worked after their mission is over, along with their regular South African wages of about $200 a month.

But this is far below the Alberta minimum wage of $11.20 per hour, and Ms. Notley said she is disturbed by the discrepancy. She vowed that they will be paid at least the legal minimum.

The South African agency, which receives government funds to provide firefighting jobs for 5,000 young people, said the 300 firefighters had signed formal contracts accepting the $50 daily allowance.

“To have a dispute about remuneration, and to be accused of being unfair towards our people, is a direct contradiction of our company values,” the agency said in a statement on Friday.

“We are extremely disappointed that we couldn’t resolve this internally before it escalated to become an international incident. We are currently investigating the matter internally and wish to apologize to both the Canadian government and Canadian citizens for any inconvenience this may have caused. We are treating this matter with the utmost importance and are committed to finding an amicable solution.”

The agency said its overseas firefighting missions have “never been about making money.” It did not comment, however, on Ms. Notley’s complaint that it was paying below the minimum wage.

After less than a week on the job, the firefighters went on strike Wednesday in a pay dispute with their South African employer. All of the firefighters have been “demobilized” since the strike, and some or all of them will be flown home, their managers say.

The firefighters arrived in Canada last month, singing and dancing as they landed at Edmonton airport, gaining media attention across Canada and internationally.

Now they’re angry that they are receiving the small allowance during their Canadian deployment, in addition to their South African salaries, despite promises of additional money.

In Calgary on Thursday, Ms. Notley said the firefighters need to be paid at least the minimum required by Alberta law. She said the province is paying $170 daily for each South African firefighter, as well as providing food, accommodation and travel costs.

“It’s not acceptable to me and to my government that we would have people working for wages in our province that do not align with our labour laws,” she said. “Every hour that every firefighter from South Africa, or anywhere else, has worked on these fires will be compensated in accordance with our laws in this province.”

It’s unclear how many of the firefighters will be returning to South Africa, since it will depend on the wildfire situation in Alberta.

Working on Fire said last week the firefighters would be getting a pay increase because of Canadian concerns that the South Africans would seem to be “slave labour” if they were paid substantially less than Canadian firefighters, who receive up to $26 an hour.

A statement by the South African organization said there was “confusion” among the firefighters after media reports of the promised pay increase.

“We are dispatching a senior management team to Alberta this evening to address the firefighters’ concerns and to assist with the smooth demobilization of our firefighters and their safe return back home to South Africa,” the statement said.

The $170 Alberta is paying daily also covers administration and training, explained Kim Connors, the executive director of the Canadian Interagency Forest Fire Centre, the non-profit responsible for bringing the South African firefighters to Canada. Mr. Connors said only the South African employers could explain how the money was being allocated.

The dispute began just north of Fort McMurray when a team of 60 South African firefighters met with one of their managers on Tuesday morning. A local contractor working with the team described the meeting to The Globe and Mail. Because Alberta’s forestry department has warned contractors that speaking with the media will lead to being barred from future contracts, the man has asked that his identity be withheld.

At the impromptu meeting in the field, the crew of firefighters learned that their pay wouldn’t be $50 daily, as many believed, but only $15, with the remainder paid out once they returned home. A similar setup existed in the past when a smaller number of South African firefighters were deployed in Canada, and some contend they were never paid the balance of their wages when they returned home.

“It was pretty clear that within minutes they had a mutiny on their hand,” the contractor told The Globe and Mail.

Early Wednesday morning all 300 firefighters went on strike. They were only on the fifth day of a 14-day work schedule, followed by three days of rest and one day of travel.

More than 2,000 firefighters are now working on the Fort McMurray wildfire. Most are from Canada. Because the 300 South Africans left the fireline Wednesday, there have been reports of staffing shortages.

The pay dispute is focused on two issues: the timing of the deployment allowance of $50 a day, and the question of parity with the wages of Canadians.

On the first issue, the South African firefighters want to receive the entire daily allowance during their deployment. Their managers argue that the firefighters should receive most of the $50 daily allowance after their return home, so that they don’t waste it on higher expenses in Canada.

On the second issue, a manager said last week that the firefighters would receive a higher amount this year – the equivalent of about $15 to $21 an hour. He said the Canadian officials had requested that the South African firefighters receive a wage similar to Canadian firefighters.

Some of the South African firefighters, learning of this statement, were angered that their $50 daily allowance is far less than the $21 hourly pay that they expected.

On Wednesday, the South African managers gave a different account. Trevor Abrahams, a board member at Working on Fire, said the pay “increase” is mostly derived from the higher “value” of their Canadian pay this year, due to currency fluctuations and the lower cost of living in South Africa compared to Canada.