Police say around 10:00 pm, they stopped a car at 63rd and Oxford for driving erratically.
During the stop, officers got suspicious after smelling marijuana and alcohol on the driver.
The driver was asked to get out of the car and further investigation revealed other 'suspicious' items inside the vehicle.
Subsequently Philadelphia police called Homeland Security and the FBI.
A preliminary investigation revealed that there were no explosives or chemicals found in the car
Police have not said what those items were that raised suspicions.
The suspect, who is not an American citizen, is believed to have been in town for a conference in the area.
Police are working to determine when he arrived in the country and how long his intended stay was for.
The suspect remains in custody.