DENVER (AP) — Federal authorities are cracking down on the use of exploding targets on U.S. Forest Service land in five states to prevent them from sparking wildfires.

Monday's order covers forest and grasslands in Wyoming, Colorado, Kansas, Nebraska and South Dakota. Violators could face a fine of up to $5,000 and be sent prison for up to six months.

Exploding targets can be purchased legally. They're used for shooting practice and explode when hit by a bullet.

According to the Forest Service, they've caused at least 16 wildfires nationally in the last year. In the five state region, they're blamed for starting seven since the beginning of 2012. The largest was Springer Gulch near Colorado's Lake George. It cost $2.7 million to fight.

The Bureau of Land Management is considering a similar ban.