Action News has learned that six rental vans were unaccounted for dating back to September 1st.
This all came to light when police called local rental outlets, looking for reports of missing vehicles.
Those calls were made during homeland security investigations in light of potential terror threats in New York City and Washington, D.C.
During those calls, they discovered six missing vehicles. Five have now been accounted for, with the discovery of two of the stolen trucks leading to an evacuation in the Kingsessing section of Philadelphia on Tuesday morning.
12th district police officers recovered the first two stolen U-Haul vehicles in the 5400 block of Trinity Street - the other on the 5300 block of Chester Avenue.
30 people were evacuated from their homes while a five block radius was cordoned off for the investigation.
Police were concerned because these types of vehicles have been used in the past as truck bombs or to transport explosives.
A bomb sniffing dog from the K-9 unit and the bomb disposal unit were called in, but no sign of explosives were found in the vehicles.
The third vehicle was found shortly after 7:00 a.m. on the 3200 block of N. Park Avenue in North Philadelphia.
Police now say the fourth and fifth vehicles were rented and were returned, but were not logged as such.
The final missing U-Haul truck was discovered Tuesday night at Chadwick and Reeds streets in South Philadelphia.
The recovered U-Haul vehicles were towed to the Philadelphia police garage where they will be dusted for fingerprints. A full investigation will be conducted, including involvement from Homeland Security.
Police had said earlier Tuesday that they believed the trucks had been stolen on 9/11. They later clarified to say that the trucks were discovered to be missing due to heightened vigilance surrounding the 10th anniversary of the 9/11 attacks.