Ali Moustafa, 29, and seven others were killed Sunday when a pair of explosive devices were dropped in a rebel-held part of Aleppo, Syria.
The photographer’s sister, Justina Rosa Botelho, confirmed her brother’s death after viewing a photo of his corpse that was sent to her by activists.
"He just wanted the world to know about human rights and all the horrible things going on down there," Botelho said in a telephone interview with The Associated Press. "He was passionate for the world to know."
The family was not aware that he was in Syria. They were last in contact a week ago, when Moustafa told her that he was in Turkey, she said.
"He wanted to tell mom he was okay," she said. "He never told me he was in Syria. I guess he was trying to hide that."
Botelho said she and Moustafa shared the same mother.
She said that Moustafa was due to return to Toronto, the city in which he was born, within weeks.
An activist who identifies himself as Abu al-Hassan Marea told The Associated Press that a military helicopter dropped a so-called barrel bomb on the Hadariyeh area of Aleppo, on Sunday. After reporters and others moved in to survey the damage, a second bomb was dropped, leaving Moustafa mortally wounded.
Barrel bombs dropped by Syrian military helicopters have also been extremely deadly for civilians, because they cannot be precisely targeted. The bombs in Aleppo have killed hundreds of people after blowing apart homes, vehicles and shops, and caused thousands to flee their neighborhoods.
Justin Podur, a Toronto-based activist, remembered Moustafa in an online post as a passionate photographer and activist who "was no hotel journalist."
"Pretty much everything I ever saw him do, he did with this motivation. He never put himself above the people he was writing about. He put himself with them, instead."
Maher Azem, a friend of the deceased, received word of Moustafa’s death from two friends who phoned him.
“It was a very devastating experience,” Azem told CBC News Network on Sunday afternoon.
Azem said he met Moustafa when the photographer expressed interest in going to Syria.
"He was introduced to me by another friend and he was interested in going and covering the story of refugees in Syria," he said.
Azem said that Moustafa had initially travelled to Syria last year, and wanted to show the world that the people living there "deserve to live."
Moustafa had given an interview to a journalist in July of last year, explaining that he had gone to Syria in March of 2013, after previously travelling to Israel, the Palestinian territories and Egypt.
"I felt it was important to go there to cover the war firsthand," Moustafa told the publication. "In a way, I'm also fascinated by war not in the gory sense but in the way it impacts us as human beings. What does it take away? What does it leave behind? Most importantly, what does it transform us into?" he said.
A vigil is supposed to take place in downtown Toronto at 7 p.m. ET on Sunday, at Yonge and Dundas streets.
Journalists face danger
Syria is the world's most dangerous conflict for reporters.
Since the Syrian uprising began in March 2011, dozens of journalists have been kidnapped or killed by both forces loyal to President Bashar Assad and rebels seeking his overthrow.
The most vulnerable journalists have been freelancers who do not have companies providing them with safety training, equipment or insurance. Moustafa sold photographs to the photo news agencies EPA and SIPA. Representatives of both companies said he had only worked with them briefly.
Also Sunday, nearly 130 organizations called for immediate and permanent humanitarian access to civilians throughout Syria to help relieve the immense suffering caused by the country's civil war.
The 128 groups making the appeal include United Nations agencies and relief organizations from around the world.
In a statement released Sunday, the groups urged all sides in Syria's conflict "to listen to the voice of the international community as expressed unanimously through the Security Council."
A UN Security Council resolution last month called on Syria's warring sides to facilitate aid deliveries. The UN says more than 9 million Syrians are in need of humanitarian assistance.
Many of those most in need live in areas under government-imposed blockades, while others are in territory under the nominal control of rebel groups.