Police said Wednesday they are looking for a man who yelled “bomb” on an L train over the weekend, causing an unnecessary subway scare.

The man was on a Manhattan-bound L train at about 5:45 p.m. on Saturday, police said. When the train left the Bedford Avenue Station in Williamsburg, the man yelled “bomb,” counted down from five and yelled “bomb” a second time, they said.

A passenger on the train took a photo of the man before getting off at the First Avenue Station, cops said.

The man, believed to be between 30 and 40 years old, is described as 5 feet 10 inches. He was last seen wearing a white T-shirt and blue plants, police said.

The incident occurred the same day a bomb exploded in Chelsea, injuring at least 29 people. Ahmad Khan Rahami was arrested and charged for the bombing.