The Fayette County Public Schools canceled all student activities and searched high school buildings Wednesday after three crude "pop bottle" bombs were found on a parking lot behind Lafayette High School.
One of the bombs exploded about 8:30 a.m., causing no injuries. The other two were deactivated.
Searches turned up no bombs at other schools, and no arrests were made, school district spokeswoman Lisa Deffendall said Wednesday afternoon.
When the bottle exploded early Wednesday, members of the Lafayette marching band's color guard were practicing on the parking lot behind the school, Deffendall said.
Tim Hall, a volunteer band chaperone who was present, estimated that color guard members were about 25 yards from the bottle when it exploded.
"I heard a loud pop like a firecracker, and everybody was trying to figure out what it was," Hall said. "There was this plastic bottle that clearly had been the cause of the sound, and there was liquid that had sprayed out of it."
He said the bottle was sitting against the wall of the school building.
Hall said he had noticed the other two bottles on the parking lot when he arrived at Lafayette earlier, thought they were trash, and put them in the back of his pickup truck.
"I'd forgotten I put them there," he said. "When it popped, I said to myself, 'That's what those bottles are in the back of my truck.'"
Members of the full Lafayette band started arriving for a band camp practice session scheduled for 9 a.m., Deffendall said. Lafayette band director Chuck Smith learned of the situation, heard sirens approaching, and moved the band inside the school, she said.
"It's just disappointing that someone would do this," Hall said.
Although crude, pop bottle bombs can injure people close by. They've never before turned up at a Fayette school, Superintendent Tom Shelton said.
City police said at least six people have been injured by such devices placed in mailboxes and similar locations in Lexington over the past few years.
Injuries occurred when people were hit by bottle shards or were burned by chemicals, or inhaled chemical fumes, police spokeswoman Sherelle Roberts said. Injuries can depend on the materials used in the devices, Roberts said.
It wasn't clear when the bottles were placed at Lafayette.
Shelton said school officials will check surveillance camera footage in hopes of identifying those who placed the bottles.
No warning phone call or social media message was received by the school, Shelton said.
Pop bottle bombs do not contain conventional explosives, and they aren't sophisticated. They are generally made by placing a chemical product in a plastic bottle with some water.
A buildup of pressure can cause the bottle to explode.
"It's unfortunate that someone could find something like this on the Internet," Shelton said. "They probably think they are playing a prank, but they are actually creating a very serious situation where someone could be seriously injured."
"Our best advice is that if you see anything suspicious, report it but don't touch it."