A group of protesters bearing guns, American flag and some wearing military camouflage uniforms and masks gathered outside the Islamic Center in Irving, Texas Saturday to "stop the Islamisation of America."

They were protesting the Obama administration's decision to allow the entry to the U.S. of thousands of Syrian refugees.

Organizer David Wright and his group, the Bureau of American Islamic Relations, picketed outside the centre to also protest rumours that there's a Sharia court at the mosque, according to the Dallas Morning News.

Wright said they brought weapons "mostly for self-protection."

"But I'm not going to lie. We do want to show force. We're not sitting ducks," he said. "We don't want people to think we're out to kill people or shoot people."

Wright said he also heard a rumour that local Muslims threatened Irving Mayor Beth Van Duyne who supported a state bill blocking Muslim influence in the U.S. court system.

The protest was held a week after the terror attacks in Paris that killed at least 130 people.

City Council member David Palmer talked to the protesters after a mosque member told him about the gathering.

"Does it look like there's any threat here? Nobody's even close to them," he said.

Palmer said the show of force was used for intimidation.

"My initial impression was they were using them for intimidation. I doubt that they'd be happy if some of the Muslim churchgoers here showed up at their Christian church, their Baptist church, their Methodist church tomorrow morning with rifles slung over their shoulders," he said.

The Islam Center of Irving denied that there is a Shariah court at the mosque.

"The management of the Islamic Center of Irving categorically declares that no such court operates on the centre's premises. However, there is an Islamic Tribunal that operates in the Dallas-Fort Worth Metroplex to address a genuine need within our faith community for intra-community arbitration," the centre said in a statement posted on its website.

Dr. Zia Sheikh, the leader of the centre, participates in his individual capacity in the Islamic Tribunal as an arbitrator, it said.

"These religious tribunals are optional arbitration vehicles that only conduct their work when requested to do so by both parties involved in a dispute, do not attempt to impose any belief system upon any individual and work in compliance with State of Texas and U.S. law under the United States Constitution," the centre said.

The centre also condemned the Paris attacks on Nov. 13, saying it "expresses its deepest sympathies to the people of France for the attacks in Paris."

"Our condolences go out to the families and loved ones of the victims. We also strongly condemn and denounce the attacks, as they have absolutely no basis in the religion on Islam. We sincerely hope that the perpetrators, whether they were directly or indirectly involved, are brought to a swift justice," it said.