Brian Milligan Jr. poses with his girlfriend, Nicola Fletcher, before he was attacked last month.
NEW YORK (CNN) -- Brian Milligan Sr. believes his son's race triggered a brutal attack on the streets of Buffalo, New York.
Armed with a chunk of concrete, several assailants beat Brian Milligan Jr. on the back of the head on August 18, leaving a 3-inch gash. They kicked him in the face, breaking his jaw.
Bloodied and bruised, the 18-year-old managed to walk five blocks to his grandmother's house before being rushed to the hospital.
Milligan's father believes several African-Americans beat his son, who is white, because he is dating an African-American woman. He wants police to treat the beating as a hate crime. He also has criticized what he calls a deafening silence from the community, police and the national media.
"If this was a black guy who was beaten by a group of white guys for dating a white girl, people would be up in arms," he said. "There's a double standard."
Buffalo police believe a group of about 10 to 15 African-American men attacked Milligan late at night, police spokesman Mike DeGeorge said. Police have made no arrests and are still investigating the motive, he said.
Milligan Sr. says he believes the attackers are the same "neighborhood guys" who threatened his son and his African-American girlfriend because of their interracial relationship.
The younger Milligan and his girlfriend, Nicola Fletcher, who is also 18, had recently complained of an increase in insults and threats in east Buffalo, where Fletcher lives and where Milligan was staying with his grandmother, Fletcher said.
"Every time they walk the streets, people stop him and call him 'cracker' and ask her why she's not with a black guy," Milligan Sr. said.
Two days before the attack, Fletcher said she was shot with paintball pellets by the same group of neighborhood aggressors.
"I'm afraid to walk the streets," she said. "Those guys are still out there."
Police "are making good progress in the case," said DeGeorge, the police spokesman. Investigators are still trying to determine if it should be declared a hate crime.
They have asked members of the community to call police if they have any information.
When Milligan was taken to Erie County Medical Center, he was unconscious and suffered blood on the brain and brain swelling as a result of the beating. He will see a neurosurgeon on September 10 to be evaluated, said his father.
He is now recovering at home and remembers nothing about the attack, which has made the police investigation even more difficult.
The story has touched a nerve with several members of Buffalo's African-American community, including a local pastor who leads a predominantly black church in Buffalo.
"At first, it didn't affect me the way that it would have if I heard it was a black teen attacked," said the Rev. Darius Pridgen, who spent years fighting for civil rights for African-Americans.
"But after I saw his father on TV pleading with the community to find the assailants, I decided I had to go after the people who beat this kid."
Pridgen said he felt that the community has turned a collective blind eye to the beating. So he gave a fire-and-brimstone sermon at the True Baptist Church on a Sunday after the attack, appealing to his congregation to help find the culprits.
"He didn't deserve to be beaten this way," Pridgen recalled saying at the service. "If you believe this, put your hands together."
If it was a black teen, Pridgen said, "We would have been protesting with flags and everything else."
Rod Watson also addressed the issue in his column in the Buffalo News. Watson, who is black, pointed out that interracial marriages are nearly 10 times higher than they were in 1960, according to U.S. Census data, but still those couples have a tough time being accepted by society.
Judy Milligan, a community activist and Brian Milligan Jr.'s great-aunt, said she has been overwhelmed with support from her friends, both black and white.
Mary Woods, a member of Buffalo's African-American community, reached out to Milligan to offer her support.
"I don't care what color you are, when something like this happens, justice must be served," Woods said. "There had to be someone who saw something, and they should come forward."
Milligan Sr. has criticized the Buffalo Police Department for spending too much time "trying to prove this crime wasn't a hate crime instead of performing a solid investigation."
But DeGeorge said the department is pursuing the attackers with the same vigor as it would any crime.
"People tend to want crimes solved yesterday," DeGeorge said. "We are performing a thorough investigation and that takes time."
He expressed optimism that Buffalo residents would come forward to help bring the perpetrators to justice.
Milligan lies in a hospital bed. The attack broke his jaw and left a 3-inch gash on his head.