Kennewick — Kennewick police are investigating a rash of “Drano bomb” explosions that have blown up four mailboxes.

Drano bombs involve placing drain cleaner in a plastic bottle with some tinfoil. The chemical reaction of the hydrochloric acid and the tinfoil in the confined space causes an explosion, said Kennewick police.

Four incidents have occurred involving the bombs — all within a few blocks of each other:

At 8 a.m. Jan. 16, a resident at 2905 S. Garfield St. reported that his mailbox blew up. When the officers arrived, they found the remnants of a Drano bomb. No injuries were reported.

On Thursday, officers investigated a similar incident at 1102 S. Newport St.

At 5:30 p.m. Monday, the resident at 2905 S. Garfield St. discovered that his new replacement mailbox had been destroyed again by a Drano bomb.

At 5:30 p.m. Monday, a resident at 1700 S. Olympia St. reported that their mailbox had been blown up and it appears to have also been the result of a Drano bomb.

While no one appears to have been injured in any of the explosions, the potential for serious injury or death is always a possibility, said Kennewick police.

“We are asking parents to examine their cleaning supplies and determine if they have drain cleaner recently missing and in particular if they have teenagers in the house. We have reason to believe that the suspect(s) in these cases may live in the area of the crimes. It is important to put an end to this activity before there is a serious injury,” said Sgt. Ken Lattin in a press release.