Updated: 06/12/16 : 06:20:54Printable Version
Security is being enhanced at metro stations in Los Angeles after a "specific" threat of a terror attack close to a major Hollywood theme park.
The FBI says the threat was made on an anonymous tip line and passed on to the US Joint Terrorism Task Force by an international partner.
The call was made by a man speaking English who threatened an attack on the "off-ramp" at the Universal City/Studio City Red Line metro station to the north of Los Angeles, about half a mile from the Universal Studios attraction, on Tuesday.
Authorities say they have not established if the call is credible but decided to go public because of the specificity and the imminence of the threat.
The FBI, the Los Angeles police and sheriff's departments say they will step up security on the metro system, with an increase in uniformed and undercover officers on duty.
LA Mayor Eric Garcetti told a news conference he would board a Red Line train at the Universal City metro station on Tuesday to reassure the public they should go about their day as usual.
The red and purple lines carried around 145,000 passengers a day.
Authorities say they are acting out of "an abundance of caution" and have stressed the threat is "non-corroborated".
Major employers in the area around Universal City have alerted staff to the warning and the potential for an increased police presence in the area.
Deirdre Fike, the FBI's assistant director for Los Angeles, told reporters that law enforcement already take an increased "threat posture" during the holiday season but that she was confident their actions in this incidence were appropriate.
Authorities in Los Angeles were criticised last year for their response to a bomb threat made to the city's schools.
They were accused of over-reacting after immediately closing all schools in the city, causing chaos a thousands of students were forced to find a way home just after classes should have begun.