Anti-Islam protesters have planned a “Draw Muhammad” rally outside an Arizona mosque once attended by the gunmen responsible for the attack on a similar event in Texas earlier this month.

The event is timed to coincide with the Friday night communal prayer, jummah, at the Islamic Community Center in Phoenix. Rally participants are encouraged to bring guns to the event, despite the organizer’s claim that it is a “peaceful” protest.

Jon Ritzheimer, the event organizer, said that event is meant to “expose Islam” and to send a message “to the known acquaintances of the two gunmen”.

On 3 May, Elton Simpson and Nadir Soofi opened fire with assault rifles and shot one security guard outside a Muhammad cartoon contest, sponsored by the American Freedom Defense Initiative (AFDI). A police officer on duty shot and killed both men, who had stopped attending the Phoenix mosque before the attack.

“Everybody has a right to be a bigot,” Usama Shami, the president of the mosque, told 12News. “Everybody has a right to be a racist. Everybody has a right to be an idiot.

“They’re not looking for an intellectual conversation,” Shami said. “They’re looking to stir up controversy, and we’re not going to be a part of it.”

He has encouraged members of the mosque to still attend the Friday prayer, and law enforcement have been warned about the rally.

It will be the third protest orchestrated by Ritzheimer since the Texas shooting. Protest attendees, including Ritzheimer, are known for making hateful statements at the demonstrations and for wearing shirts that say “f*** Islam”.

CNN’s Anderson Cooper asked Ritzheimer on Thursday night whether he was playing into the narrative propagated by extremists that there is a war between Islam and the west. “Sure,” Ritzheimer said. Moments later, he added: “I don’t believe in a war.”

Of the more than 3,700 people invited to the event on Facebook, 300 people had said they are going as of Friday morning.

The Council on American-Islamic Relations (Cair) has requested that the FBI investigate threatening letters sent to the Phoenix mosque and another mosque in the city’s suburb of Tempe.

Imraan Siddiqi, chairman of the Phoenix chapter of the Council on American-Islamic Relations, said that the group has received an outpouring of support from people around the country. He said that people from other religions, and those who do not hold any religious beliefs, have contacted the group to say that they are sorry the Muslim community has to experience the attention of the protest.

He believes that there may be more counter-protestors than anti-Islam protestors at the rally. “We are not inviting people to go out there, because tons of people are going to be carrying weapons, but there are some interfaith groups, like Christian groups, and groups from other organizations that want to stand-up for the Muslims, who are going out there,” said Siddiqi.

He said law enforcement warned Cair about the event and that it has worked alongside community leaders to discuss how to prepare for the rally. “Here, a group of armed individuals wanting to a community who are just trying to worship, practice freedom of religion, showing up there with guns, this is the most horrific situation you could imagine in America,” Siddiqi said.

Simpson stopped going to the mosque a few months before the shooting, after attending it regularly for about 10 years. Soofi stopped going to it about a year ago and had attended infrequently before that.

Some rally attendees will assemble at a local Denny’s before the event, and there is an afterparty scheduled at a nearby biker bar.