It's not your typical traffic alert.
"It will total your vehicle. You're talking anything from maybe 500 hundred pounds up to maybe 1500 hundred pound animals," said Lieutenant Stephen Englert with the Susquehanna Regional Police Department.
Drivers in East Donegal and Conoy Townships are being warned of cattle roaming along a major road in Lancaster County.
"We just don't deal with this many being out at one time," said Lieutenant Englert.
The cows were spotted along Route 441 over the weekend by more than half a dozen people. Susquehanna Regional Police believe there may be more and aren't taking any chances. They've put barricades and signs on Monday cautioning drivers of cattle on the road.
"Only in Lancaster County," said Charlotte Marrello, a frequent driver on Route 441.
Police say they're not sure where they came from. They've checked with area farmers who say all their cattle is accounted for.
"Unfortunately this is a unique situation where we can't locate them and we just want to people to be a little more aware of them," added Lieutenant Englert.
But drivers like Marrello say it's not something they're used to.
"I mean deer are one thing you should know to have to pay attention to deer during deer season. Cows are always around so what are you supposed to do to protect yourself from that," added Marrello.
As a result, police are urging drivers to slow down.
"I'm recommending maybe 35 miles an hour and obviously keep your eyes open for any animals."