WAUPUN, Wis. (AP) -- Waupun police are investigating a string of at least 10 bomb threats that have forced local establishments to evacuate and left local residents skittish about going downtown.
Reports say police are frustrated because they have to take each threat seriously, and their responses tie up emergency resources.
Bomb threats have been called in to fast-food restaurants, grocery stores, convenience stores and a high school.
The threats began Sunday night. Police Chief Dale Heeringa says no devices have been found, but the community gets rattled every time there's another rush of police sirens.
He says descriptions of the caller's voice vary, and the number that shows up on caller ID appears faked.
A $200 reward was raised to $400 following a threat Wednesday at Waupun Area High School.