HUTCHINSON, Kan. (AP) — A loud boom that startled some residents in south-central Kansas was caused when damaged fireworks that were being destroyed exploded.

Steve Showalter, owner of Showalter Fireworks, says employees placed three or four damaged fireworks in a burn pit early Tuesday, and they all went off at the same time.

The Hutchinson News reports the boom from about a pound of black powder in the fireworks caused houses to shake and set off residential alarms, prompting several 911 calls to Hutchinson police and other agencies.

Showalter says his business has used the same method to destroy damaged fireworks for years and no one was ever in danger. He says the lack of wind and high humidity were good conditions for carrying the sound from the explosion.