Support for the Islamic State group may be spreading in the Philippines, according to recent reports. Pictured: Iraqi security forces and fighters gather next to a mural depicting the ISIS emblem April 1, 2015. Getty Images

The Islamic State group may be gathering strength in the Philippines, an island nation with a history of Muslim rebellions. The Japan Times reported Wednesday that there are signs of rapidly accelerating support for the terrorist group, aka ISIS, specifically in the southern Philippines. The government in Manila, however, has dismissed the extremists as simple criminals.

“They are spreading here,” the Rev. Sebastiano D’Ambra told the Times, speaking from Zamboanga. “God knows what will happen next. Everybody is trying to maintain control of the situation, but I am afraid that sometime, in some way, it will go out of control.”

D'Ambra's comments come days after several Filipinos released a video depicting members from various insurgent factions declaring their loyalty to ISIS leader Abu Bakr al-Baghdadi. Among them was the Abu Sayyaf group, a militant organization that operates primarily in the southern part of the country.

Abu Sayyaf is one of the Philippines' biggest Muslim separatist groups, along with the Moro National Liberation Front and Moro Islamic Liberation Front. They've been waging insurgent attacks for decades in hopes of autonomy, but the latter recently began a peace process with the government, the Washington Post reported. About 5 percent of the Philippines' 98 million people are Muslim.

The video renewed concerns about whether the organizations would set up a wilayat, or ISIS satellite, in the Philippines. But authorities insisted they weren't worried.

"The local militants are only interested in making money, and those attracted to Islamist ideology would rather travel to Syria and Iraq, especially those from Malaysia and Indonesia," an anonymous intelligence source told Reuters this week. "What we have in the south are pure criminals hiding behind IS masks to gain prominence and raise more ransom money."

In the past, ISIS has formally recognized wilayat provinces in places like Libya, Saudi Arabia, Egypt and Yemen, according to Filipino news site Rappler.