The robbery happened around 9:45 a.m. in the 7200 block of Torresdale Avenue.
According to police, two men armed with assault rifles robbed the Brinks truck, and sources say the men fled in a blue getaway car.
Police believe they have located the getaway vehicle near Front Street and Fairmount Avenue in Northern Liberties. A blue Acura SUV was towed from the scene.
Action News learned that the truck was parked at the Torresdale bus loop and was servicing a Budget Financial Center at the time of the robbery.
Chopper 6 was over the scene, where the truck was seen pulled over on the side of the road.
No one was injured and no one is in custody.
The area is a busy business district. Police are talking with witnesses at the scene.
"We can see from our point of view was arguments and the car just took off on the sidewalk. That's what I saw," one witness told Action News. "And then, of course, when the cops came, that's when they said we need to see the cameras. The store got robbed at gunpoint."
The FBI is now leading this investigation, sources said.
This is a developing story and will be updated.