Lobbyist Jack Burkman was attacked in front of his Arlington home Tuesday evening, police said. (Bill O'Leary/Washington Post)

A conservative lobbyist known for his controversial positions was attacked and sprayed with a "caustic substance" outside his Arlington home on Tuesday evening, according to police.

Arlington police say an investigation is ongoing and that there is no indication yet who may have been behind the attack on Jack Burkman, a Republican strategist and radio host perhaps best known for his attempts to ban gay men from becoming National Football League players following Michael Sam's 2014 entry into the league.

On Tuesday evening, Burkman said in an interview, he walked to the grocery store, a short distance from his quiet Arlington street a few blocks from the Potomac. He purchased items for dinner and went home, so lost in his own thoughts that he said he didn't notice the dark SUV in his driveway until he was about 30 feet away.

As Burkman tells it, a man in a black jacket got out of the SUV on the passenger side and, as he came around to the front of the car, put on a mask that "looked like something you would see in one of the movies of a bank robber."

He had something in his hand, and Burkman said he thought, "The end is coming."

Instead, Burkman said the man sprayed him with what he thought may have been pepper spray. The man yelled an obscenity at Burkman, struck him in the head and, as Burkman screamed and stumbled, got back inside his SUV and drove off. Burkman said he wasn't sure if there was another person in the car.

"It looked professional, but who knows," Burkman said.

Burkman said he couldn't pinpoint who could have been so upset at him for the simple fact that he has upset so many people in his life. "You could have 10 different causal nexi," he said.

Burkman has long been a fixture in Washington. After promoting the anti-gay ban in the NFL, he came back into public view when he offered a $130,000 reward for help solving the murder of Seth Rich, whose 2016 slaying sparked conspiracy theories that percolate to this day. Burkman launched a website devoted to the conspiracy and argued Rich could not have been killed in an attempted robbery, as the police and Rich's family have said he probably was.

The Tuesday attack came just hours after Burkman played a role in another high-profile event. In a court appearance in the fraud and conspiracy case against former Trump campaign official Rick Gates, Gates was rebuked by a judge for appearing in a video shown at a fundraiser that Burkman had organized to raise money for Gates's legal defense. U.S. District Judge Amy Berman Jackson had earlier ordered Gates to show why his decision to appear in that video hadn't violated a gag order and to specify his relationship with Burkman.

Afterward, Burkman had issued a statement criticizing Jackson, accusing her of carrying out a "one-woman crusade against free speech. . . . Is this Germany, 1943?" Jackson declined to comment through a spokesman.

Shortly after the attack, Burkman dispatched two news releases and even organized a news conference. He said he isn't leveraging the alleged attack for publicity, but for safety and to protect his family.

"If it's professional, you want to get the message out," he said.