Deah Barakat, 23, his wife Yusor Mohammad Abu-Salha, 21, and her sister Razan Mohammad Abu-Salha, 19, were fatally shot Tuesday in Chapel Hill, North Carolina. 

Their neighbor, Craig Stephen Hicks, 46, surrendered to police after the attack and has been charged with three counts of first-degree murder.

“This murder is a reflection of the Islamophobia that grows day by day in the U.S.,” said Mahroh Jahangiri, organizer of the Friday’s prayer event.

The FBI announced Thursday night that it launched a “preliminary inquiry to determine whether or not any federal laws were violated related to the case” in addition to an ongoing case currently being conducted by local authorities.

“The FBI has a history with a Muslim community that is predominantly bad,” said Adam Sbita, the preacher who led the prayers. “I think this is definitely an opportunity for the FBI to come out and do the investigation correctly, look at the facts and the power that they have to use to prove that this was indeed a hate crime.”

Hicks identified himself as an atheist on Facebook, and used the social media site to criticize multiple religions, including Christianity and Islam.

In his first comments about the killings, President Barack Obama denounced the “brutal and outrageous” murders in a statement Friday, saying, “No one in the United States of America should ever be targeted because of who they are, what they look like, or how they worship.”

The families of the victims have said that they think the case should be investigated as a hate crime.

“I think it is important to recognize that the Muslim community feels that this is a hate crime and so it should be investigated as such,” said Jahangiri. “Whatever the details that came out of investigation, I think the underlying issue is that Muslims feel unsafe and vulnerable in this country and that is a much larger problem that hasn’t been recognized enough,” she said.