About 600 people fled the Kraft Foods management center in Tarrytown Thursday after a Vietnam War-era mortar shell was found.

The Westchester County Bomb Squad evacuated the workers from 555 South Broadway at around 11:30 a.m. after police said a maintenance worker found the 18-inch device in a closet.

The mortar shell had two pounds of explosive material inside, but the firing mechanism had been removed.

"It was not in any danger of exploding, our investigation revealed the device has been in the building for a number of years," said Tarrytown Police Chief Scott Brown. However, officials added that damage would have been disastrous if it had exploded.

During their initial investigation, police discovered that the mortar shell had been making the rounds at Kraft for about two years, even winding up on people's desks before getting tucked away. There's no word on who brought in the potentially dangerous device.

Authorities allowed workers back inside about 90 minutes later.