At first, firefighters were not sure if it was a potential danger. That's why they asked about 20 people to leave their homes in a one block radius around the fire station. They also shutdown several street blocks around the station.
Firefighters called the Vermont State Police bomb squad which examined the grenade.
"It is inert so it's no danger to anybody. But our precaution is until we absolutely know that...we bring the EOD (Explosive Ordinance Disposal) in," says Chief David Bergeron, Winooski Fire Department.
Police say the woman was a business owner who had received a bag of military memorabilia. Once she looked in the bag, she saw the grenade and, on what turned out to be bad advice, took it to the fire department.
Police say they don't believe the woman had any malicious intent.
They ask anyone who finds something potentially dangerous, including a grenade, to call police and not take the object anywhere.
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