– Journalists and activists in Morocco during the heady days of the Arab Spring knew Anas Haloui, a slight, serious, wispy-bearded man in his 30s who would bombard them with e-mails about the plight of jailed Islamists.

Unlike many Salafis, as followers of his ultraconservative strand of Islam are known, he was eager to engage with people who didn't share his beliefs.

But one day in December 2013, Haloui left behind his wife and children and quit Morocco to join a group linked to ISIL.

"I love my country with my last breath, but I was a victim of injustice," he said in a letter of farewell.

His older brother, Yusuf, remembers a different Anas — one who enjoyed singing. He recalls a cheerful boy in a family of eight kids growing up in the foothills of the Rif mountains.

Haloui attended Fez University, but after the 2003 Casablanca suicide bombings by young Islamic radicals that claimed 45 lives, Haloui dropped out and returned home. His efforts to distance himself from his student activism were in vain. He was arrested and convicted of forming an extremist group and spent three years in prison. When he got out in 2007, he was a changed man, his brother said.

The 2011 Arab Spring demonstrations in the region inspired Haloui. He joined the protests with secular activists. Morocco got a new constitution promising greater freedoms. But the police soon returned to their old habits. One day men in plainclothes picked up Haloui's fiancée, slapped her around and warned her against marrying him.

"After this his personality changed," said his brother. "His dreams were shattered."

Haloui's attention turned to the bloodshed in Syria.

"We know it is a war of extermination and that the only way to stop them from harming the innocents is through arms, God may one day ask us where we were during the Syrian events," he said in his goodbye letter.

In April 2013, his family learned through Facebook that he had died on a Syrian battlefield.