HALIFAX -- Prime Minister Justin Trudeau confirmed Thursday his government is responding to a desperate plea from the grieving mother who lost all seven of her children in a recent house fire, saying he wants to "give this family a little solace in a time of unbelievable tragedy."

Kawthar Barho, whose husband Ebraheim is in a medically induced coma to recover from extensive burns, has told local politicians and religious leaders in Halifax that she wants to be reunited with family members living overseas because she has no other relatives in Canada.

The prime minister, in Halifax on Thursday for a funding announcement, said Halifax MP Andy Fillmore had already contacted Immigration Minister Ahmed Hussen about expediting the immigration process for some family members.

"I can't comment on specific cases, but in heartbreaking cases like this we're certainly looking at doing what we can to bring this family that has suffered such a devastating loss together," said Trudeau, who attended a vigil in Halifax's main square Wednesday night in support of the Barhos.

The Barhos arrived in Nova Scotia with their children as privately sponsored refugees in September 2017.

Early Tuesday, a fast-moving fire killed all of their children: Ahmad, 14; Rola, 12; Mohamad, 9; Ola, 8; Hala, 3; Rana, 2 and Abdullah, who was born in Canada on Nov. 9.

The cause of the fire remains unclear.

Fillmore said immigration applications were being reviewed Thursday.

"This is an absolute priority to get this done as quickly as possible," he said. "I think it's absolutely critical that we get those family members here as quickly as we can."

The Liberal MP said he had met with Kawthar at the hospital, where she was asked if there was anything federal officials could do to help.

"She made it clear that it was her family," Fillmore said.

Natalie Horne, vice-president of the community group that sponsored the Barhos' refugee claim, said some family members from Syria have already registered with the UN refugee agency, which should help speed up the process.

Typical refugee claims can take several years to complete.

"Once (the Barhos' story) leaves the headlines and people go back to their lives, there's still going to be a wake of tragedy for Kawthar and for Ebraheim," said Horne, vice-president of the Hants East Assisting Refugees Team.

"It will be a long road to recovery ... It's really important for us to get family here who can support them on that journey."

Horne said Kawthar Barho told her the fire was caused by an electric baseboard heater that ignited a couch.

However, deputy fire Chief David Meldrum said residents should be wary of reading too much into that kind of speculation.

"We're aware of the reports that are in the media, as well as other information on social media," Meldrum said in an interview. "I want to remind everyone this information is not coming from official sources. Our investigation is ongoing."

Meldrum said if the investigation uncovers anything that would affect community safety, that information will be released to the public as soon as possible.

Still, he said it was unclear how long the investigation would take.

Ehab Zalok, an expert in fire safety engineering at Carleton University in Ottawa, said the fact that neighbours heard a bang before flames spread rapidly through the house suggests something non-solid, like a gas, may have caused the fire to spread rapidly.

He said the scale of the fire, which destroyed much of the home's top floor, suggests it was "much more than just (a) structure burning or furniture burning" because that kind of fire usually takes longer to grow.

"If you have something burning for a few minutes you would expect that people will smell something like smoke, smoke alarms will sound -- something to prepare people for what's coming, which is a bigger fire," he said in an interview.

A funeral for the children is expected either Friday or Saturday, said Imam Abdallah Yousri of the Ummah Mosque in Halifax.

Though the mosque can hold about 2,000 people, Yousri said the ceremony will be moved to a larger venue. That site had yet to be selected by Thursday afternoon.

The Barhos had lived in the Halifax suburb of Spryfield for only a few months, having moved to the city from nearby Elmsdale, N.S., to take advantage of language training and other immigrant services. They had planned to return to Elmsdale next month.

Neighbours say the children missed their old school and the friends they had made there.

The Barho family was among 1,795 Syrian refugees who have come to Nova Scotia in recent years.

The Trudeau government granted asylum to 40,000 Syrian refugees in 2015-16.

A brutal civil war has raged across Syria since 2011, claiming more than 400,000 lives.

With files from Brett Bundale and Holly McKenzie-Sutter