The phone threat targeted the Universal City station — located near the Universal Studios theme park — where the caller said something would occur on Tuesday, FBI LA field office Assistant Director Deirdre Fike told reporters.

The Los Angeles Times quotes a law enforcement official as saying the caller threatened to blow up the station.

Fike said authorities were working to determine the credibility of the threat, described as “very specific,” and that security had been stepped up at the station as well as other transit stations across the area.

Los Angeles County Sheriff Jim McDonnell urged commuters to remain vigilant and report any suspicious activity.

He said undercover deputies would be deployed throughout the network along with uniformed officers.

Mayor Eric Garcetti urged commuters to go about their lives as normal despite the threat and said he planned to ride the metro on Tuesday to allay fears.

Los Angeles has a metro system that consists of six lines, including two rapid transit subway lines and four light rail lines that serve 93 stations.

The Universal City station has been listed as among the busiest in the network.

It also has a large bus transport system.

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