Had things gone according to 21-year-old Khalil Abu-Rayyan's plan, a 6,000-member church in Detroit would soon be the site of a massacre. Federal authorities have arrested the Michigan man, who confessed to being an ISIS supporter and outlined an attack that he had been planning for some time, according to NBC News.

Abu-Rayyan has been under online surveillance since May 2015 after his activities on social media had been noticed by authorities. He was quite active in the world wide web, supporting extremist videos with likes and re-tweeting ISIS-related links as much as he could.

What really nailed his coffin, however, was when he made "increasingly violent threats" during monitored phone conversations and electronic communications with an undercover federal agent. During that time, he clearly stated his desire to commit acts of terrorism on American soil, reported Israel National News.

The most prominent threat he has made was his alleged plan to initiate a mass shooting on a church in the nearby area. Abu-Rayyan did not name the church, but he stated that it was one of the biggest in Detroit, with a congregation of about 6,000.

His plans, however, never came to fruition, as his paraphernalia, including the weapons he was planning on using, were discovered by his father.

"I had it planned out. I bought a bunch of bullets. I practiced a lot with it. I practiced reloading and unloading, but my dad searched my car one day and he found everything. He found the gun and the bullets and the mask I was going to wear," he said, according to the Daily Mail.

After he was arrested, Abu-Rayyan told authorities that he wished his plan had come to fruition.

"Honestly, I regret not doing it. If I can't do jihad in the Middle East, I would do my jihad over here," he added. 

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