Waterford — The suspect in what appears to be a string of convenience store robberies continued to elude investigators Tuesday after robbing yet another store.

Tuesday’s target was the Henny Penny at 26 Norwich Road (Route 32) in the Quaker Hill Section of Waterford. It was the fourth successful robbery at Henny Penny in southeastern Connecticut since Thursday.

A white male wearing a black mask, jeans and hooded sweatshirt entered the store at 7:53 p.m. and demanded money from the frightened store clerk, said Waterford Police Lt. Steve Bellos. No weapon was displayed and no injuries were reported but the clerk was shaken up by the incident, he said.

The suspect left with an undetermined amount of cash. A witness at the scene reported seeing the man leave in a gray, older model Audi-type vehicle with tinted windows and no license plate visible.

No injuries were reported.

Police cordoned off the entire property surrounding the store and searched the parking lot for evidence while sending a BOLO, or “Be On the Lookout,” to area agencies with a description of the vehicle.

Groton Town police detectives joined Waterford investigators at the scene because of the likelihood of sharing information, Bellos said. The Henny Penny on Route 12 in Groton was robbed on Thursday, the first in the string.

“We believe they are all connected,” Bellos said.

Thursday’s robbery in Groton was committed by a white man wearing a hood, sunglasses and yellow gloves. He displayed a handgun tucked into his waistband to the store clerk.

Shortly before 8 p.m. on Saturday, a man fitting the description in the Groton robbery, yellow gloves included, attempted to rob the Sunoco gas station at 715 Colman St. in New London. The man did not obtain any cash.

An hour later, however, Stonington police were at the scene of a robbery at the Henny Penny at 2 Roosevelt Ave. in Mystic. Again, a white male wearing a black sweatshirt was able to make off with cash.

The latest robbery before Tuesday’s occurred Monday at 8:30 p.m. at the Henny Penny on Route 12 in the Gales Ferry section of Ledyard. The suspect was wearing a dark hooded sweatshirt, jeans, dark gloves with yellow trim, a green knit hat, work boots and a scarf.

Bellos said the descriptions of the suspect, the timing of the robberies and other factors have led investigators to suspect the same suspect. He said convenience stores will continue to receive extra scrutiny during patrols.

He said the fact that the targets were nearly all Henny Penny convenience stores may only be a coincidence since they are ubiquitous in the area. It is also unclear if bank robberies in Stonington and Ledyard on Monday and Tuesday are related.

g.smith@theday.com

Twitter:@SmittyDay