WHITEMARSH TOWNSHIP, Pa. (CBS) – A second delivery driver in as many months was tied up and violently robbed in the same area in Montgomery County. The latest incident happened Tuesday on Militia Hill Road in the Plymouth Meeting section of Whitemarsh Township.

Whitemarsh Township detectives say it is highly unusual to have two violent robberies happen in the last two months in the same area. They also say the crimes have several similarities.

Police say the latest incident involved a courier driver who was flagged down by a man who asked for directions near Militia Hill Road around 4 a.m. on Tuesday.

The driver stopped but then another man appeared, pulled out a gun and the two suspects got out zip ties. They then forced the driver into the back of his truck, police say.

The suspects then drove to Whitemarsh Avenue where the contents inside the truck were taken and put into an SUV that a third suspect was driving.

A similar incident happened in the same area last month where another delivery driver was robbed. In that case, those suspects posed as police officers.

Police are investigating if either incidents are connected.

"Obviously the similarities and the location lead that to play, but we're checking both things out right now," Whitemarsh Township Police Lt. Greg Keenan said. "The circumstances were different, one was a police impersonator, one was a stop in a random parking lot, but obviously we're checking all of our leads at that point."

Jeff Butler saw the crime scene and said police asked for video captured by his security cameras. The video may be the only clue detectives have.

"My camera captured a vehicle exiting the scene from the top of the street and going fast to the bottom of the street," Butler said.

In the first robbery in May, the suspects stole medication, mostly pain killers. It's not known yet what was stolen this time.