Authorities in the US state of North Carolina are trying to determine whether hate played a role in the shooting deaths of three Muslim students.
Craig Stephen Hicks, 46, was charged with three counts of first-degree murder on Wednesday in the fatal shootings of Deah Shaddy Barakat, 23, his 21-year-old wife, Yusor Mohammad, and her sister, 19-year-old Razan Mohammad Abu-Salha.
Thousands of people are expected to attend a prayer service and the funeral of the three victims later on Thursday.
Authorities said the preliminary investigation of the shooting in Chapel Hill, North Carolina showed that a long-simmering parking dispute was the motive, but family members insist it was a "hate crime".
"This was not a dispute over a parking space, this was a hate crime," Mohammad Abu-Salha, the father of the two slain women, told the News & Observer newspaper .
"The media here bombards the American citizen with Islamic, Islamic, Islamic terrorism and makes people here scared of us and hate us and want us out. So if somebody has any conflict with you, and they already hate you, you get a bullet in the head," Abu-Salha, who is a psychiatrist, said in another interview.
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The campus at the University of North Carolina Chapel Hill has never witnessed scenes like it as thousands of students gathered for a silent candle lit vigil.
Church bells peeled across the grounds as students stood in silence, some weeping, as a big screen displayed pictures of Deah Shaddy Barakat, his wife Yusor and her teenage sister Razan.
The images were of happier times: Deah and Yusor's recent wedding and the kind of selfies that young people across the world take. It was a sombre scene but a show of unity that this small university town will not easily forget.
Students of all faiths joined hands and comforted each other over a loss deeply felt across this entire community. The three students were all leading lights in their chosen fields and generous with their time in helping others.
Suzanne Barakat, sister of Barakat, appealed to authorities on behalf of her family, saying "we ask that the authorities investigate these senseless and heinous murders as a hate crime".
Gerod King of the Bureau of Alcohol, Tobacco, Firearms and Explosives said that agents were in touch with the US attorney's office in North Carolina that encompasses Chapel Hill and that investigators had not ruled out a hate crime.
"We understand the concerns about the possibility that this was hate-motivated, and we will exhaust every lead to determine if that is the case," Chapel Hill police Chief Chris Blue said in an email to reporters.
The cautious wording of the police statement contrasted sharply with the anguished reaction among some American Muslims who viewed the homicides as an outgrowth of anti-Muslim opinions.
Outrage was voiced on social media with the hashtags #MuslimLivesMatter and #CallItTerrorism.
"Based on the brutal nature of this crime ... 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," Nihad Awad, of the Council on American-Islamic Relations, said in a statement.
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Vigils for the victims were being held on Wednesday night in North Carolina and elsewhere around the US.
Barakat and Mohammad were newlyweds who helped the homeless and raised funds to help Syrian refugees in Turkey this summer.
Abu-Salha was visiting them on Tuesday from Raleigh, where she was studying.
Imad Ahmad, who lived in the condo where his friends were killed until Barakat and Mohammad were married in December, said Hicks complained about once a month that the two men were parking in a visitor's space as well as their assigned spot.
Both Hicks and his neighbours complained to the property managers, who apparently did not intervene.
"They told us to call the police if the guy came and harassed us again," Ahmad said.
Hicks, who appeared briefly in court on Wednesday, is being held without bond. Police said Hicks turned himself in and was cooperating.
Source: Al Jazeera and agencies