HICKSVILLE, N.Y. (CBSNewYork/AP) — A group of sophisticated burglars used tools to penetrate a vault of a Long Island armored car company and steal $1.8 million, but were foiled by an alert police officer.

The burglary at the Loomis Armored Inc. warehouse in Hicksville occurred around 10:30 p.m. on Aug. 16.

The men, who wore masks, used a sledgehammer and a hydraulic jack to bust through thick concrete walls and used other tools to break into the vault that held about $20 million, authorities said.