The Milpitas Police Department said officers responded to the Great Mall just after 5:30 p.m. PT after reports of an altercation where someone brandished a knife. Shortly after, a shooting was reported inside a Burlington Coat Factory store.
Officers checked the store and there was no indication a shooting took place inside and no victims related to the initial call have been found, the department said.
"Due to conflicting information, we are in the process of checking the entire mall out of an abundance of caution," a police tweet read. "At this time we have not located nor have any reported victims related to the initial call regarding the knife or shooting."
Several law enforcement agencies responded to the scene and were assisting with a search of the mall. Shoppers and store employees who sheltered in place were being escorted outside, police said.
Video shared to social media purportedly captured the scene outside.
Fox News has reached out to county authorities and the mall.
Social media users said the mall had been locked down and evacuations were ongoing. Some videos show people walking out of the mall with their hands on their heads.
Others showed people who said they were told to hide.
The Valley Transportation Agency tweeted that light rail service would bypass the stop at the mall because of law enforcement activity.