A mall in downtown San Francisco was temporarily put on lockdown Sunday evening following a massive brawl that left a police officer injured and several people detained.

The San Francisco Police Department received multiple 911 calls at around 6.43pm about a violent melee at Westfield Mall located at Market and Fifth streets.

Cellphone videos recorded by bystanders at the scene and later shared on social media captured people running in panic and screaming inside the mall crammed with shoppers and dozens of responding police officers.

Massive melee: Westfield Mall in downtown San Francisco became the scene of a massive fracas Sunday evening

Heavy police presence: Dozens of uniformed cops responded to the shopping center after getting 911 reports about a brawl in progress

This screenshot from a witness' cellphone video shows an officer swinging what appears to be a nightstick at a young man

Cellphone videos recorded by bystanders at the scene and later shared on social media captured officers struggling to subdue brawlers

One video shows an officer swinging what appears to be a nightstick at a young man, while several of his colleagues nearby struggle to subdue another person.

A second recording shared on Twitter shows a large number of cops tackling someone on a moving staircase.

Multiple Twitter commenters used the term 'riot' in describing what happened inside the mall Sunday evening.

The scuffle reportedly broke out between two dozen people in the food court area of the mall and then escalated, drawing dozens of police officers to the scene, according to NBC Bay Area.

Officer Robert Rueca told KRON4 that as cops attempted to detain brawlers and restore order, some bystanders physically assaulted them and hurled objects at them.

The mall was briefly placed on lockdown as a precaution, then closed early

One officer suffered minor injuries and multiple people were detained after the fracas

The scuffle reportedly broke out between two dozen people in the food court area of the mall and then escalated

According to the police, one officer sustained minor injuries when he was pepper sprayed during the fracas, and one juvenile was arrested. Some local reports said a number of people were detained in the wake of the violent clash.

The mall at 865 Market Street was briefly placed on lockdown as a precaution, then shuttered for the night ahead of scheduled.

The affray took place after Sunday's Gay Pride Parade, but police said they do not believe the incident involved a hate crime. The cause of the punch-up is under investigation.

The shopping center was expected to resume normal operations and reopen on time Monday morning.