Story highlights Hassan Hanafi spied on fellow journalists and identified those with negative opinions of Al-Shabaab

After joining the terror group, Hanafi killed or helped kill journalists

He was promoted within Al-Shabaab and fought against Somali and African Union troops

(CNN) For years, Hassan Hanafi was a trusted source of news in Somalia. As the voice of Holy Quran Radio in Mogadishu, listeners across the capital tuned in to hear him report the latest political news.

But at some point, Hanafi turned his interest from journalism to terrorism -- and joined Al-Shabaab

He used his media connections to spy on and betray fellow journalists, identifying reporters with negative opinions of Al-Shabaab and facilitating assassinations. He even carried out assassinations himself, a military court ruled.

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Hanafi was convicted of murder and sentenced to death. On Monday, shortly before a firing squad executed him, Hanafi released a statement saying he wanted to die as a martyr.

"Today, I'm being killed in the way I chose, which was to die for the sake of Allah," he said. "I don't fear execution."

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