SAN FRANCISCO -- "Chilling" video images surfaced online Saturday showing an officer at a California university calmly pepper-spraying a line of several sitting protesters, who flinch and cover their faces but remain passive with their arms interlocked as onlookers shriek and scream out for the officer to stop.

The chancellor of the University of California, Davis said she was forming a task force to investigate, even as a university faculty group called for her resignation because of the incident Friday.

"The use of the pepper spray as shown on the video is chilling to us all and raises many questions about how best to handle situations like this," Chancellor Linda Katehi said in a message posted on the school's website.

The officers' reaction to the protest, held in support of the overall Occupy Wall Street movement, and the ensuing video images, which were circulated on YouTube and widely online, prompted immediate outrage among faculty and students, with the Davis Faculty Association saying in a letter Saturday that Katehi should resign.

She was expected to speak at a news conference later Saturday.

Images of police evictions have served to galvanize support during the Occupy Wall Street movement, from the clash between protesters and police in Oakland last month that left an Iraq War veteran with serious injuries to more recent skirmishes in New York City, San Diego, Denver and Portland, Ore.

The forcible Oakland protest eviction, the first of its kind on a large scale, marred the national reputation of the city's mayor and police department.

It's not clear from the video what agency the officer who used the pepper spray represents. Officers from UC Davis and other UC campuses as well as the city of Davis responded to the protest, Annette Spicuzza, UC Davis police chief said.Davis is about 80 miles north of San Francisco.

Spicuzza told the Sacramento Bee that police used the pepper spray after they were surrounded.

"There was no way out of that circle," Spicuzza said. "They were cutting the officers off from their support. It's a very volatile situation."