A jury yesterday convicted a gangster and his accomplice of a deadly botched mob hit in a bar 12 years ago.

In a Bronx courtroom packed with extra security staff, jurors declared Joseph Meldish, 54, guilty of gunning down Joey Brown in Frenchy’s Tavern in Throggs Neck in 1999, although prosecutors said he was probably targeting the victim’s brother, Thomas, who had a feud with the gunman.

Cops have said they think Meldish and his accomplice, Kimberly Hanzlick, 45, meant to retaliate against Thomas Brown after Meldish was arrested on robbery charges.

Hanzlick was convicted of helping Meldish carry out the mistaken-identity murder.

Meldish — a reputed member of the Purple Gang, a drug-dealing group tied to the Genovese, Luchese and Bonanno crime families — will be sentenced March 9.