Boston police have been asked by the FBI to look out for a yellow Penske truck with an unidentified driver, according to emergency services radio scanner chatter.
The dispatcher has advised officers to “approach with caution.”
The truck apparently attempted to deliver medical supplies near the marathon earlier in the day but was turned away.
The police now want to stop the driver for “FIO,” a term that means “Field Interrogation and/or Observation Report.”
It is not clear what role the police suspect the truck may have played, if any. Police appear to be pursuing a number of random leads and suspicious person calls from earlier in the day.
When asked about a truck at a press conference later in the day, Boston police commissioner Edward Davis said they were not looking for a specific truck but were pursuing all leads.
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