RNA - The incident happened in an apartment near the University of North Carolina at Chapel Hill campus on Tuesday.
The victims are Deah Shaddy Barakat, his wife Yusor Mohammad Abu-Salha, and her sister Razan Mohammad Abu-Salha.
All were involved in humanitarian aid programs.
Students at UNC, where Yusor Mohammad was going to join her husband as a student later this year, were gathering on Wednesday for an evening vigil and prayer service.
In a statement, police said they responded to a report of gunshots in the usually quiet area of Summerwalk Circle in Chapel Hill at 5.11pm local time on Tuesday. Upon arrival, officers found the three young individuals, who were pronounced dead at the scene.
People on social media quickly reacted to the shooting, posting pictures of the victims and claiming they had been “murdered execution style.”
Two hashtags went across twitter by the social network users, #chapelhillshooting and #MuslimLivesMatter.
On tweet said, “Muslim victims were recently seen providing free dental & food supplies to the poor & homeless."
“If a Muslim executed 3 Christian students in US, it would get a LOT more media coverage than I'm seeing right now,” another tweet said.
Barakat, 23, Yusor, 21, and Razan, 19, were all shot in the head.
Some users urged US President Barack Obama to condemn the incident, comparing the shooting to the Charlie Hebdo shootings in Paris.
Barakat, who was active on social media, posted a tweet about the crisis in the besieged Gaza Strip about two weeks ago.
"It's so freaking sad to hear people saying we should 'kill Jews' or 'kill Palestinians.' As if that's going to solve anything SMH," he tweeted.
Meanwhile, the Council on American Islamic Relations (CAIR) condemned the shooting deaths of the Muslim students.
In a statement on Wednesday, the Muslim civil liberties advocacy group urged police to address the speculation about the suspect’s motive.
“Based on the brutal nature of this crime, the past anti-religion statements of the alleged perpetrator, the religious attire of two of the victims, and the rising anti-Muslim rhetoric in American society, we urge state and federal law enforcement authorities to quickly address speculation of a possible bias motive in this case,” CAIR National Executive Director Nihad Awad said.
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