Police were sent to several “suspicious bottles” along the MBTA Fitchburg line in Concord, Massachusetts.
Anti-bomb robots are believed to be examining a second device, local media claim.
Bomb squads are investigating 'possible chemical reaction bombs'
It remains unclear how many bottles were found on the tracks or what chemicals were in them.
A source told NBC Boston that someone had placed the chemicals in the bottles with the intention of causing an explosion.
Concord police, fire services and Massachusetts state police have all been deployed to investigate the bottles on tracks near Sudbury road.
No bottles were hit by the trains.
Trains have been held at Concord due to police investigations. Customers have been told to expect severe delays.
— ConcordMAPolice (@ConcordMAPD) March 7, 2017
Police have given trains permission to run though one track near Concord at reduced speeds.
More to follow...
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