The family of a Nigerian man who died on a flight while being escorted out of the country is hoping a passenger saw something and will come forward.

On August 7th, the 49-year-old man got into what the Canada Border Services Agency describes as an exchange with two agents.

Bolante Alo was removed from a KLM flight to Amsterdam, went into medical distress and later died in hospital.

“This is a family that lost a loved one, so they're quite broken about the death but also about the manner  of death because there is very little information that has come through, there is very little known about what caused his death,” says Elias Munshya the Alo family’s lawyer.

The Calgary Police Service is investigating this case as a death in custody but right now details of what happened on that flight remain unclear.

Alo arrived in Canada in 2005 and had fought to remain in Canada filing numerous times for refugee status.

“He was not looking for handouts, all he was appealing for was for an opportunity to remain in Canada and save his life because he believed that in Nigeria his life was in danger,” says Munshya.

Documents from the Immigration and Refugee Board of Canada warned removing Alo could be “violent” and advised CBSA agents to “take caution” and “be careful”.

Alo had a wife and two sons aged 17 and 20 in Nigeria.

A GoFundMe page has been set up by his church in the hopes of raising enough money to send Alo’s remains back to Nigeria.

“It will help them find some closure,” says Munshya. “It will help them to have the body of their departed husband and father.  It will be very good to take his remains back to Nigeria so that he can be interred there.”

An autopsy did not confirm a cause of death and it can take months to do additional testing.

Two agents did suffer minor injuries in the incident.

The CBSA is conducting an internal investigation.

(With files from Brenna Rose)