California professor Loay Alnjaji is arrested on involuntary manslaughter charge for death of Jewish protester Paul Kessler

California police have arrested Loay Alnaji on an involuntary manslaughter charge for the death of Jewish protester Paul Kessler. 

Kessler, 69, died after getting into an altercation with Alnaji at a protest in Thousand Oaks earlier this month. 

An autopsy revealed he'd been hit in the face and died after hitting his head on the concrete sidewalk. Witnesses said Alnaji attacked him, causing him to fall. 

Alnaji was taken into custody today by The Ventura County Sheriff's Office. 

He is being held on a $1million bond. 

Police continue to appeal to anyone who captured their altercation on video. 

At the scene, Alnjai was filmed telling a police officer he was trying to hit Kessler's phone away. 

But witnesses including Kessler's friend, Jonathan Oswaks, say he punched him with his megaphone. 

'All of a sudden, I see a punch...the white megaphone flying through the air,' Oswaks, speaking at the scene of the protest last week, said. 

Oswaks implored the police to act sooner. 

Alnaji stayed at the scene after Kessler was taken away in an ambulance. He later cooperated with police at his home. 

Videos taken after he fell show Palestine supporters continuing to chant against Israel, and some making antisemitic remarks about Hitler.