Fire crews were called out to investigate a suspicious device found near the trolley tracks by J Street and I-5 Chula Vista Fire confirmed.
The call came around 2 p.m. and crews are working to clear the device.
MTS is running a bus between the H Street Station and Palomar as the track is fully closed between the two stations. Passengers can expect a 20 to 30 minute delay on the Blue Line.
No other information was immediately available.
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