It all began when a worker arrived at the M&T Bank branch at 1817 Street Road in Bensalem around 8:25 a.m. and found a gift-wrapped box hanging from a side door.
Bensalem Public Safety Director Fred Harran says the employee brought the package inside.
Once there, that person found it had a note that read "This is a bomb and it will explode by cell phone."
"It gave her some directions on getting money and she would get a phone call on where to put the money," said Harran.
The Philadelphia Bomb Squad was called to the scene. Officers with the bomb squad say they detonated two live pipe bombs which were rigged to a cell phone.
The blast damaged a window on the front of the bank, but there were no injuries.
"This was not a hoax. This was an actual device with a cell phone attached to it which could have been set off remotely," said Harran. "There was not a lot of active powder, it wouldn't have done much damage, but it was a real device. "
Harran said this was an unusual method for staging a bank robbery.
"This was an absolute robbery attempt as if they walked in and left a note on the counter," said Harran.
Police say there was evidence gathered at the scene, but did not say what the evidence was. There did not appear to be any cameras pointed at the area where the package was left, police said, so there may not be any video of a suspect.
As a precaution, the Bensalem School District put four surrounding schools on lockdown for about 45 minutes.