One held a gun on staff while the other smashed glass cases with a hammer, police said. View Full Caption NYPD

MANHATTAN — Two masked men held up a Madison Avenue jewelry shop at gunpoint and stole more than $300,000 in watches Monday morning, NYPD officials said.

The entire heist was caught on a surveillance video released by police Tuesday morning, showing the pair walking into Jaeger-LeCoultre at 701 Madison Ave. and immediately pointing their guns at staff and ordering them to the ground, according to police and the video.

One of the suspects is shown in the video standing guard while the other takes a claw hammer to two glass cases and reaches in through the shattered glass to snatch the timepieces inside.

The thieves took five watches worth more than $300,000 and fled east on 62nd Street, police said. They hadn't been arrested as of Tuesday morning, police said.

One stands about 6-foot-4, weighs 240 pounds and was wearing a black winter coat, black dress pants, a baseball cap and sunglasses, police said.

The other is about 6-foot-2, roughly 200 pounds and was wearing a gray winter coat, a multi-colored ski cap, black pants, black Nike boots and black sunglasses, police said.

Anyone with information should contact Crime Stoppers at (800) 577-TIPS (8477).