Fairfax County police are continuing to investigate how an explosive device ended up in a vacant Franconia townhouse Monday evening.

Police responded to the townhouse in the 6500 block of Gildar Street, after a cleaning crew discovered what is described as an “unusual looking box with tape and wires.”

The county’s explosives unit removed the device, police said.

The house is currently on the market.

Anyone with information on the incident os asled tp call police at 703-691-2131 or report tips anonymously via Crime Solvers at 1-866-411-8477.

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