Thieves broke into the Upper East Side home of fashion designer Shoshanna Lonstein Gruss and stole $1 million worth of jewelry, sources said.
Gruss, who dated Jerry Seinfeld from 1993 to 1997 — starting when she was 17 and he was 38 — returned home from vacation on Tuesday and discovered a closet door open and a safe broken into, the law enforcement sources said.
A door on the roof of the home, at 118 E. 61st St., was broken.
Gruss’ Instagram page features photos of her and her children frolicking on the beach in Montauk, LI, where she was vacationing.
She told police that the family left for the holiday on June 25.
Gruss is the founder of the fashion label Shoshanna, which makes elegant dresses and swimwear.
She married Joshua Gruss, the son of financier Martin Gruss, in 2003, and they divorced in 2014.