(AP) — Nebraska officials estimate that last weekend’s tornadoes caused at least $20 million damage across the state.

The Nebraska Emergency Management Agency said Tuesday that part of the reason why the damage estimate is so high is that Sunday’s storms caused extensive damage to power lines.

The storm cleanup effort continued Tuesday as resident and volunteers worked to pick up fallen tree limbs and building debris.

The eastern Nebraska towns of Beaver Crossing, Cordova and Sutton sustained some of the most extensive damage.

But Sunday’s storms damaged homes, businesses and farms across a large area between Hastings and Omaha.

NEMA officials say it appears that the storms spawned at least a dozen tornadoes Sunday. But National Weather Service officials are still examining the damage to classify the storms.