Sloppy spelling ain’t no crime, but for one hapless would-be Israeli bank robber, a revealing typo recently proved to be his undoing, landing him (back) behind lock and key.

Leonid Dmitryenko entered a post office (which in Israel also offers banking services) in the coastal city of Ashdod and slipped the clerk a note, Israel’s Channel 10 television news reported on Wednesday.

“This is a robbery. Giv [sic] me 20,000 shekels or I will throw a grenade,” the (Hebrew) note read.

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The clerk was uncowed by the threat, the TV report said, prompting Dmitryenko to flee the scene empty-handed. Footage aired by the station shows a disgruntled man in a baseball cap, apparently unarmed, walking away from the counter.

When investigators arrived minutes later, it was the typo and formulation of the letter, rather than any security camera footage or forensic evidence that quickly led them to their suspect.

Back at the police station, they dug up a note used three years earlier under similar circumstances: “This is a robbery. Giv me 30,000 shekels now or I will stab someone here.”

Dmitryenko served a three-year prison sentence for the previous robbery, the TV report said. He was arrested and remains in police custody pending charges for this attempt.