The online "hacktivist" group Anonymous published the personal contact details on Monday of a California university policeman who used pepper spray on protesters, and it urged supporters to flood him with phone calls and emails.
YouTube videos of Friday's incident on the campus of the University of California, Davis have gone viral and led to the suspension of the college police chief, two police officers and calls for the chancellor to step down.
In the YouTube videos, one of which has received 1.44 million views, two university police officers in riot gear are seen spraying an orange mist on protesters sitting peacefully on the ground.
Following the spraying, the crowd begins chanting "Shame on you!"
A YouTube video on Monday purportedly from Anonymous published the home address, the home telephone number, the cellphone number and the email address of one of the policeman who allegedly used the pepper spray on protestors.
In the video, an artificially altered voice tells the "police forces of the world" that "brutalization of our citizens is both unjust and uncalled for."
Specifically addressing the officer involved in the Davis incident, it said: "You are a coward, and a bully."
"Flood his phones, email and mailbox to voice your anger," it said.
A call to the cellphone number listed identified it as that of the police officer involved and said his voicemail box was full.
Anonymous has been involved in scores of hacking exploits including the recent defacing of a website of Syria's Ministry of Defense to protest a bloody crackdown on anti-government protestors.
Last year, the shadowy group launched retaliatory attacks on companies perceived to be enemies of the anti-secrecy website WikiLeaks.
Explore further: Snowden, Assange top bill at Texas tech gathering (Update)