It was a strange and scary one that didn’t get away.

Lawrence resident Sean Un was fishing Monday afternoon at Mary’s Lake, a popular fishing hole for Lawrence children, when he reeled in a 20-pound pipe packed with gunpowder.

The pipe was about 16-inches long and two inches in diameter and had three slender propane tanks attached to the outside with duct tape.

It was a pipe bomb.

“I was scared to death,” said Un, 49, who’s been fishing since the 1970s. “It looked like someone was up to no good.”

Un didn’t have a phone on him, so he left the bomb lying on the side of the lake, told people in the area not to touch it, and walked to a phone to call police. Lawrence Police came to the scene and eventually called for the Olathe Fire Department’s bomb squad to destroy it.

Capt. Ed Schons Jr., commander of the bomb squad, said it appeared someone may have ignited the fuse, then tossed it in the water. But the fuse stopped just short of igniting the powder.

“I don’t know if they were just building it to mess around or if it was a prank or what,” he said. “They could have just been experimenting with this thing to see what it would do. I don’t know.”

The pipe was closed on either end with threaded metal caps, he said. Despite having been underwater, the device was still “extremely dangerous” because whoever built it took steps to keep the gunpowder from getting wet, he said.

Campers from the Prairie Park Nature Center fish at Mary's Lake on Tuesday morning. The lake was shut down Monday evening after a man reeled in a pipe bomb.

“Had it gotten any kind of spark or flame inside that pipe … it could have gone off,” Schons said. “Potentially, friction can cause gunpowder to go off, too.”

Un said he fished at Mary’s Lake, east of 31st Street and Haskell Avenue, about once a month. He isn’t sure if he’s going back.

Jeff Morris, a resident of the nearby Prairie Park neighborhood, happened upon the scene Monday as he was on his way to go fishing at the lake with his three children and a nephew.

“My first thought was, ‘My God, how many more of them are down there that we don’t know about?'” he said.

6News video: Fisherman makes alarming catch

Morris, 38, said he wouldn’t be surprised if someone was using the bombs to fish.

“I’ve seen a lot of dead fish on the banks lately,” he said.

Sgt. Dan Ward, a Lawrence Police spokesman, said police didn’t have any information that would lead them to believe there were more sunken bombs in the lake, and he said the department didn’t plan to search the lake at this point.

He asked anyone with information to call the Crime Stoppers hot line at 843-TIPS (8477) or the Police Department at 832-7509.