(CBS BOSTON) – Several incendiary devices were found on national grid power lines in Tyngsboro and now the FBI is leading a multi-agency investigation into the incident.
Firefighters were called to wooded area off 60 Locust Avenue Wednesday afternoon for a small brush fire under some high-tension lines. After it was put out, they noticed something unusual hanging from the wires.
"Crews that responded to the scene noticed items that didn't appear to be part of the transmission system and alerted National Grid. National Grid assessed the situation and alerted law enforcement," FBI Special Agent in Charge Harold Shaw said in a statement Thursday.
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State Police and FBI bomb technicians found "multiple incendiary devices similar in structure to pipe bombs in the area."
At a press conference Thursday afternoon, FBI Assistant Special Agent in Charge Peter Kowenhoven said the devices were cylindrical metal objects and that they needed to be "manually activated," but would not say how many authorities found.
"There was some pre-planning in this," said Kowenhoven of the FBI. "These devices were home-made."