The girl's father, Mohmoud Hassanen Aboras of Reston, said he doesn't understand how this could have happened, because he said his daughter, 17-year-old Nabra Hassanen, was a friend to everyone.
Police charged 22-year-old Darwin Martinez Torres with murder after pulling a young woman's body from a pond.
Detectives have so far found no indication of a link "between the victim's faith or religious beliefs or the mosque and the crime itself," Fairfax County Police Spokesman Don Gotthardt told The Associated Press.
"This tragic case appears to be the result of a road rage incident involving the suspect, who was driving and who is now charged with murder, and a group of teenagers who was walking and riding bikes in and along a roadway," a police statement said.
The lack of a hate crime investigation provoked deep skepticism among some American Muslims.
Abas Sherif, a spokesman for the victim's family, said Nabra and all the other girls in her group were wearing Muslim head coverings and loose Islamic robes when the driver approached.
"Road rage. Indeed. If you think for a minute that her appearance had nothing to do with this crime, you're lying to yourself," tweeted attorney Rabia Chaudry, a prominent Muslim activist who lives in the Washington suburbs.
According to police and witnesses, the attack happened as Hassanen and her friends were walking back to the All Dulles Area Muslim Society mosque from a McDonald's in the Sterling area between 3 and 4 a.m. on Sunday.
ADAMS is one of the largest mosques in the country, and is particularly busy during Ramadan. Observant Muslims fast from sunrise to sunset during Ramadan, and since Ramadan this year overlaps with the summer solstice, and sunrise occurs well before 6 a.m., some Muslims will eat large meals in predawn hours.
Two boys in their group who spoke with The AP after paying condolences to the family on Monday said they didn't witness anything to make them think it was a hate crime. They said that when the car pulled up beside them and slowed down, they thought the driver might even be a friend, playing a joke.
Then the car hopped the curb, they perceived hostile intent and they began to run. The group of more than a dozen kids did not immediately realize Hassanen was missing. Once they did, they told security officials at the mosque, who contacted police. The boys declined to give their names.
During an intense search for the missing girl on Sunday, an officer stopped a suspicious car. The driver, Martinez Torres, was taken into custody, police said.
WRC-TV reported that Martinez Torres was questioned near the scene of the attack, and led officers several miles away to a retention pond across the street from his apartment complex where a female body, believed to be the girl's, was found at about 3 p.m. Sunday.
"What investigators told the father and the mother, he hit her in the head and put her in the car and he threw her in the water," Sherif said.
Martinez Torres was arraigned Monday and denied bail pending a July 19 court appearance. A judge appointed him a public defender, whose office declined comment. Immigration authorities put a detainer on him, saying he's a citizen of El Salvador and there's probable cause to believe he lacks permission to be in the U.S.
Aboras immigrated from southern Egypt and has three younger daughters, who like Nabra were born in the U.S. He's not particularly interested in knowing why his daughter was attacked or whether it could be considered a hate crime. His daughter is gone, regardless.
"My daughter is dead, and I don't want anyone to feel what I feel, to lose your 17-year-old daughter ... Christian, Muslim, Jew, Hispanic, whatever," he said, surrounded by more than a dozen friends and family in his apartment.
This story has been corrected to reflect that two boys, not girls, described the attack to the AP.
Contributors include Alanna Durkin Richer in Richmond.
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