A Boston-area man was arrested last week for his alleged involvement in a string of armed robberies of Dunkin’ Donuts stores, dating back to summer. Authorities used GPS technology and a surveillance plane to track the suspect’s movements in order to gather evidence to arrest him.

Isaiah Murphy, a 23-year-old former Dunkin’ Donuts employee, was charged with involvement in two robberies, but, according to WCVB-TV, investigators think he could be involved in 15 out of of 22 “seemingly related” robberies of the donuts and coffee chain stores.

isaiah murphy

Isaiah Murphy was arrested and charged with the armed robbery of two Dunkin’ Donuts shops after authorities received a search warrant and found shoes and ammunition in his home to connect him. (Image source: Canton Police Department/Facebook)

A search warrant was issued last week, but WCVB reported that a GPS tracking device and FBI spotter plane were used by investigators prior to gain enough evidence to obtain the warrant. Investigators received permission to use these devices.

Here’s more about how information was collected against Murphy, according to WCVB:

On the night of Oct. 21, officers followed Murphy for more than 2 1/2 hours. They said he appeared to suspect he was being followed, making frequent U-turns, stopping on dead-end streets and quickly popping in and out of retail lots.

Using the GPS and spotter plane, they saw Murphy return to several stores that were previously robbed. He lingered in his car nearby “as if casing them,” according to court filings.

Later, Murphy made several laps around the Endicott Variety store in Dedham before getting out and hiding in the alley. Investigators believe he planned to rob the store, the document shows.

A marked police car was sent to the area and, upon seeing it, Murphy fled, the documents say.

The aircraft then followed him to the Hyde Park section of Boston where, police say, he threw several items in two different Dumpsters.

FBI agents recovered clothing, which investigators say is consistent with clothing the suspect is seen wearing in surveillance footage from a number of the robberies, but found no weapon.

Upon receiving a warrant and searching Murphy’s home, the investigators found shoes matching what the suspect was seen wearing and ammunition consistent with that used in the robberies. A weapon was not found. Murphy’s car was also found to match descriptions of that used by the robbery suspect.

Watch WCVB’s report about the suspect’s arrest:

Murphy was fired in March, shortly after the shop in which he had worked was robbed. He was let go for being unreliable, WCVB reported.

Documents described the suspect as using “calming and apologetic language” with employees in the spree of robberies of Dunkin’ Donuts that later followed.

Canton Police Chief Kenneth Berkowitz told The Boston Globe the suspect in the robberies took a “substantial” amount of money. It is thought the suspect was not seeking revenge against Dunkin’ Donuts but more simply was using his familiarity with its operations to his advantage, Berkowitz said.

Local police, the FBI and other agencies are still investigating the robberies and following other leads.

“We are gratified to learn that the Canton police have arrested a suspect in connection with the string of robberies at Dunkin’ Donuts in the greater Boston area,” Lindsay Harrington, public relations manager for Dunkin’ Brands Inc., said in a statement, according to the Globe. “We are grateful for the diligent police work that led to this arrest.”

Last week, Murphy was being held on $200,000 bail.

Featured image via Northfoto/Shutterstock