The incident started when one of the suspects pulled out a pistol inside Omega Jewelers, at 32 Nassau St., about 6:30 p.m. Saturday, while the other suspect pushed the store's 41-year-old owner and his 15-year-old daughter into the store's back room and tied them up, the NYPD said.
The robbers then snatched jewelry from one of the display cases and fled, police said.
The father later managed to untie himself and was then able to free his daughter. Neither was injured, police said.
Police described the first suspect as a 40-year-old man, standing 6-foot-2 and weighing 175 pounds. He was last seen wearing a black North Face jacket with a purple hooded sweatshirt, police said.
Police described the second suspect as a 40-year-old man, standing 6-foot-1 and weighing 200 pounds. He was last seen wearing a burgundy leather coat with a purple hooded sweatshirt and a pair of dark sunglasses, the NYPD said.
Anyone with information is asked to call Crime Stoppers at 1-800-577-TIPS (8477).