Three men in ski masks who ran into a crowded Vons store to rob a U.S. Bank were foiled by an armed off-duty law enforcement officer.

Police say the three men stormed the Vons store at 2048 E. Avenida de Los Arboles at 6:50 p.m. Tues., March 4 in an attempted takeover robbery of the bank inside the grocery store.

"They were not trying to be discreet. They climbed on the counter and demanded money," Ventura County Sheriff's Department spokesperson Detective Eric Buschow said.

According to FBI spokesperson Laura Miller, witnesses reported the men wore black clothes, ski masks, hooded jackets, sunglasses and gloves. They were African Americans. One was 6 feet 2 inches tall, about 190 pounds, with a thin build. Another was 5 feet 8 inches, about 200 pounds, with a stocky build.

All are considered armed and dangerous, Miller said.

"They were in and out in less than a minute—they had a plan," Buschow said.

That plan went awry when an off-duty U.S. Immigration and Customs Enforcement (ICE) officer pulled out his handgun after being confronted by one of the robbers, Buschow said.

When the ICE officer drew his weapon, one of the men dropped the white mesh laundry bag of money and ran from the store with the other two men, police said.

The three got into a 2003 Dodge Intrepid with possibly a fourth person driving, Miller said.

The car was quickly found by police abandoned near the shopping center. It had been reported stolen in L.A. The men are still at large.

"This is typical of organized street gangs in central Los Angeles. They case it and try to get in and out as quickly as possible," Buschow said.

They had bank employees empty their drawers as they used threats, profanity and intimidation, then personally robbed the tellers, Miller said.

They didn't expect an ICE officer would be there, she said.

"We recovered every dollar taken," Buschow said.

Anyone with information on the bank robbery should call (805) 494-8201.

Crime Stoppers will pay up to $1,000 for information leading to the arrest and charges against the perpetrators. To leave an anonymous tip, call Crime Stoppers at 805-494-TALK (8255).