PORTLAND, Ore. -- Portland activist and former mayoral candidate Jessie Sponberg claimed he had a role in an assault on street preacher Grant Chisholm during a rally at Portland International Airport earlier this week.

Sponberg posted a message and 5-minute video on Facebook about the situation. In the video, he said the decision to "neutralize a violent situation" was not because of religion or politics, but because Chisholm was a “violent (bully) who had gone too far.” He denied Chisholm’s claims that he was hit with something metal or that a wild crowd kicked him while he was down.

Sponberg now has a lawyer and will not be speaking today. He would not clarify his role in what happened Sunday during a conversation with KGW.

He went to turn himself in at Port of Portland police at 5 p.m. Thursday.

WATCH: Sponberg arrives to speak with Port of Portland police

“Port Police are still investigating Sunday’s events. No arrests have been made," said Port of Portland spokesman Steve Johnson. He said Port Police are aware of Sponberg’s claims, and have watched his Facebook video.

It's not clear whether Sponberg actually landed the blow that sent Chisholm to the hospital.

"I don't know what's going to happen," he said. "Hopefully this will all blow over and become a teachable moment."

Cameron Whitten, another activist who recorded video of the assault, said he thought multiple people threw punches at Chisholm. He said it appeared that if Sponberg did throw a punch it didn't land very hard. Whitten suspects another person landed the heavy blow that knocked Chisholm to the ground.

“I am skeptical whether Jessie even was able to make physical contact,” Whitten said.

RELATED: Street preacher punched at Portland anti-Trump rally speaks out

Chisholm was hospitalized for two days.

Chisolm said he was at PDX to counter of the protest in opposition to President Trump's executive order banning residents of seven predominantly Muslim countries from entering the United States. He said the large crowd presented an opportunity to spread his message of repentance.

WATCH: Facebook video from Jessie Sponberg