What will bring about the end of the world? Some scientists think doomsday may result from a massive asteroid strike, an ultra powerful earthquake, or even artificial intelligence gone wild.

However, best-selling evangelical Christian author Joel Rosenberg believes that the Apocalypse will be caused by a particular group of people: Muslims.

In an interview with Fox News' Todd Starnes, Rosenberg, who authored the "Last Jihad" series, described the so-called "Apocalyptic Islam," which is a small part of radical Islam.

"We're not talking about 1.6 billion Muslims," he said in the Fox News interview. "We're talking about 10 percent or less who are radicals."

That may sound like just a small percentage, but in reality, apocalyptic Muslims constitute 16 million people—still a potent force that is out to destroy Christians and Jews.

"They want to establish their global Islamic kingdom where everybody has to follow Islam. And that is a substantively, significantly different and much more dangerous form of radical Islam than even Al Qaeda and Hamas and the Taliban," Rosenberg said.

The Christian author further warned that apocalyptic Muslims are not just contented in harming Christians.

"This is not just about attacking us," Rosenberg warned. "This is about annihilating us."

"Apocalyptic Muslims like the leaders of Iran and the leaders of the Islamic State believe that we are living in the End Times and that it's their mission from Allah to bring about the end of the world as we know it," he explained.

Apocalyptic Muslims are so savage that even terror groups like the al-Qaeda have denounced them, according to Rosenberg.

"When Al Qaeda thinks you're crazy, you're really crazy," he said. "And these people are not just crazy – they're demonic."

The best-selling author also questioned why U.S. President Barack Obama seems to be tolerating apocalyptic Muslims, particularly by consenting to the nuclear agreement with Iran.

"Once you understand Apocalyptic Islam, you understand just how dangerous it is to give Iran not just one path to nuclear weapons, but two," Rosenberg said. "This president doesn't understand the threat of radical Islam. He won't even define that – much less Apocalyptic Islam."