Washington police are warning citizens to stay away from any abandoned items in the street this Independence Day weekend -- especially tennis balls.
Authorities are warning about homemade fireworks that could be disguised as tennis balls. They are calling them "tennis ball bombs," CBS News reported.
People are reportedly taking the inside of fireworks out and then placing the explosive materials inside of other objects. Some of the materials being used include ping pong balls, pipes, and tennis balls.
"Some of them are very effective and dangerous, and some of them don't work, but you don't know," Jarod Kasner, with the Kent Police Department, told CBS News. "People light them, leave them thinking it's a dud, but who knows what's happening on the inside. Then a dog comes and picks it up..."
Such an incident occurred in 2000, when a Portland man was walking his dog and spotted a tennis ball in the grass. The man threw the ball for his dog to fetch and when the dog bit down, the ball exploded.
The dog had to be euthanized immediately.
In February, a local geocacher found this contraption at Everett's Silver Lake Park in Washington, according to KING-TV. No one was injured.
"If it doesn't go 'boom' some people just walk away from it," Kasner added. "Unfortunately, dogs pick ... everything up in their mouth and bring it to you."
Kasner also warned that the tennis ball bomb could go off in your hand.
"It could be smoldering on the inside and when you move it around that's when it goes off," Kasner said.
Police are asking citizens to avoid touching any abandoned items in the street that look burnt or have wicks or tape attached to them. They are urging people to call 911 and wait for fire officials to investigate.
"A tennis ball bomb is very easy to identify,” police said during a community meeting, according to WTVT. “It is a real tennis ball that has some sort of fuse sticking out of it. Here is a picture of one. The tennis ball could also be completely wrapped in duct tape with a fuse sticking out."
Authorities are also asking people not to play with fireworks or attempt to create their own.
"It seems cool, but it's... reckless," Kasner added.