Two robbers posing as delivery men pulled off a brazen armed heist Tuesday afternoon in the diamond district, pistol whipping an employee before fleeing the scene, police said.

The suspects, one of whom was armed, allegedly went into Watch Standard on the 8th floor of 23 W. 47th St. shop and made off with undisclosed amount of cash and merchandise around 2:30 p.m. A 56-year-old man, one of four people in the store at the time, was pistol whipped and later treated at the midtown North precinct, according to police.

After the robbery, police in SWAT gear shut down the midtown block until about 5:45 p.m. to canvass stores along West 47th Street between 5th and 6th avenues and on multiple floors.

Officers also pulled surveillance video from inside the building, police said, which was just off the route of the Veterans’ Day Parade.

A suspect dressed in a long black trenchcoat and a white button-down shirt, sporting a goatee, went inside the store to demand the loot. His accomplice, wearing a red cap and a zip-up hoodie, waited outside in the hallway, according to police.

Tony Jabaly, 48, a diamond dealer in the 23 W. 47th St. building, said SWAT teams emptied out the place.

“They shout and scream, 'Get out, get out' and we just left,” Jabaly said.

Justin Ayaz, 21,who works next door to the  store that was robbed, said he saw the daughter of the store’s boss run out frantically yelling about armed gunmen in the store.

People inside other buildings were kept inside during the search, but police started letting people out around 5 p.m.