A suspected bank robbery suspect is arrested Tuesday on the shoulder of I-270 in Maryland. (Courtesy of Don Troop)

Police arrested three bank robbery suspects in Montgomery County on Tuesday after officers set up a roadblock on Interstate 270 and walked car to car with pistols, shotguns and semiautomatic rifles drawn. The rapid show of force stunned late-morning commuters but allowed officers to nab the trio 44 minutes after the robbery.

“I guess it turned out well, so it’s hard to argue with success,” said Don Troop, who was heading to the District when traffic came to halt. A group of officers made its way to his car and other cars around him. “They were just walking along saying: ‘Pop the trunk! Pop the trunk!’ ”

Officers found the three suspects inside a silver Kia SUV, along with at least one gun thought to have been used in the heist, police said. They also found cash from the bank in a nearby dump truck, leading them to conclude that it was tossed there as police closed in. No one was injured.

“It was a good ending,” said Officer Janelle Smith, a Montgomery police spokeswoman.

Among the factors working against the suspects was the area in which they were traveling — an interstate just south of central Rockville that tends to have a large police presence. Among the agencies that quickly joined the pursuit: Rockville city police, Montgomery police, the Montgomery sheriff’s office, Maryland State Police and neighboring Prince George’s County — in a helicopter. The suspects also were on a road that could be contained once it was shut down, not a neighborhood with side streets.

“It was a combination of things,” Smith said.

At 10:02 a.m., police said, officers were called to the Wells Fargo bank branch along King Farm Boulevard in Rockville. They learned that two men armed with handguns had come in, demanded money and left with it. They got into a silver Kia, where a third man was waiting, and drove off.

A short time later, the Kia was spotted on southbound I-270. Officers in cars raced toward the area and shut down traffic in both directions.

At the time, Troop was trying to get to the District, where he is a senior editor at the Chronicle of Higher Education. Just south of the Montrose Road exit, “everything came to a halt,” he said.

He overheard a man in a truck next to him call out to another motorist: The police are looking for bank robbers. A short time later, about nine officers approached his car — including state police in tan uniforms, county police in dark uniforms and at least one plainclothes officer wearing a yellow tie.

Among their commands to motorists that Troop heard:

“Stay in your car.”

Police in Montgomery County stopped traffic along Interstate 270 on Tuesday morning to search for men who allegedly had just robbed a bank in Rockville. Police arrested three suspects and reported no injuries. Don Troop, a commuter making his way to the District from Frederick County, recorded this video. (Don Troop)

“Pop the trunk.”

“Get your hands on the steering wheel. Get you hands up where we can see them.”

Meanwhile, three officers in a helicopter had arrived from Prince George’s.

“We saw that they were searching traffic and going vehicle to vehicle,” said Cpl. Aaron Smith, the pilot. The crew spotted the Kia, became concerned that officers had walked past it and landed the craft on an empty portion of the interstate. Smith said he then helped direct officers on the ground to the Kia. Three people were apprehended at 10:46 a.m., according to Montgomery police.

Troop and other motorists were eventually allowed to continue driving, slowly, in the right lanes.

Earl Michael Kenney, 55, of Capital Heights and Michael Anthony Heard, 40, of the District have been charged with one count of armed robbery and one count of using a firearm in the commission of a violent felony. Ricko Damon Ford, 20, of Forestville has been charged with one count of armed robbery and one count of conspiracy to commit armed robbery.

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