Howard County police and firefighters are warning residents about empty plastic bottles being turned into explosive "bottle bombs," a prank that has happened five times this year and nine times in 2011.

While no one has been seriously hurt, the bottle bombs can be dangerous, officials said.

While online instructions typically say the devices are not hazardous, the bottle bombs often include corrosive chemicals that can be harmful to people, pets and the environment, police said. Those exposed to the chemicals can suffer injuries to their skin, eyes and respiratory tract.

The Howard County incidents have caused property damage, too. In February, three juveniles were investigated for allegedly using the devices to destroy mailboxes.


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Among other recent incidents: On March 9, one bottle bomb exploded near a child outside a home in the 5700 block of Thunder Hill Road in Columbia but did not injure anybody. On March 11, pieces of a plastic bottle and aluminum foil were found in a driveway in the 16600 block of Ed Warfield Road in Woodbine.

Manufacturing and detonating explosive devices, including bottle bombs, can lead to felony charges, police said.

Anyone who sees a suspicious container, which is usually a plastic bottle that has "significantly expanded and deformed," should be aware that it might be a bottle bomb about to explode and should call 911.