Mother, son and daughter charged in string of knifepoint robberies The family was arrested as a part of an undercover police operation on Saturday.

 -- A Long Island mother and her adult son and daughter were arrested and charged in connection with a string of armed robberies over the weekend, including a stick-up that occurred on Saturday, police said.

Deborah Salvatore, 55, along with her son Rick Mascia, 25, and daughter Lauren Mascia, 31, were arrested on Saturday night, accused of robbing six businesses -- one of them twice -- over the past month, police said.

The family, all of the Long Island area, was apprehended late Saturday after Rick Mascia allegedly entered a Dunkin Donuts in Coram, located about an hour east of Manhattan, with a knife and demanded money, according to a police statement.

The cashier reportedly opened the register and then ran toward the back of the store, according to the Suffolk County Police Department. Mascia then emptied the register and fled toward his mother, who was waiting for him in a getaway car parked outside, but police were already closing in on them by that point.

The two were arrested on the scene as a part of an undercover police operation, police said. The ensuing investigation led to the arrest of Lauren Mascia, according to police.

“We were able to develop investigative leads that allowed us to identify several suspects,” Suffolk County Police Timothy Sini said during a press briefing on Sunday. “We then launched a comprehensive surveillance plan and were able to catch them in the act.”

Police say the family was allegedly involved in a total of seven late-night robberies, including two Family Dollar locations and two Carvel locations. The alleged heists all took place around Long Island dating back to September 23.

Rick and Lauren Mascia were each charged with six counts of first-degree robbery. Deborah Salvatore was charged with one count of robbery in the first degree.

"They committed robberies together and now they'll go to jail together," Sini said. "It was only a matter of time that we would catch them and we did. I'm glad that we were able to catch them before anyone got hurt."

The suspects were arraigned on Saturday in Central Islip, where they all plead guilty to first degree robbery, according to ABC's New York station WABC. It was not clear if they had obtained attorneys.

ABC News' Benjamin Stein contributed to this report.