Responding authorities detonated an alleged pipe bomb Monday afternoon along Iron Horse Trail, between Hillgrade Avenue and Cervato Drive in Alamo, San Ramon Valley Fire District Spokesperson Kim French said.
The incident began when an East Bay Regional Parks District (EBRPD) ranger saw the alleged explosive and reported, French said.
It was reported at 2:10 p.m.
A witness told Danville Patch via email the EBRPD cruisers, as well as Walnut Creek police and EMT trucks were on scene.
"Police waved away walkers and bikers who approached," the witness wrote in the email. "At one point one guy dressed in a green padded suit and helmet ... appeared to be a member of a bomb squad. I also heard fire in the hole and then a short blast."
EBRPD spokesperson Emily Hopkins said the investigation into the incident is ongoing.
The alleged pipe bomb was detonated at 4:32 p.m., French said.
If anyone has any information about the incident, call EBRPD at 510-690-6549 or call the confidential line at 510-690-6521.
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