It happened around Blossom Lane and Fleur lane, according to WFMZ.
ATF officials tell Action News there was an explosion, but they can't confirm the type of device.
An eyewitness said he was cutting grass between 6:30 p.m. and 7 p.m. when he heard what sounded like an "explosion."
A resident who lives outside where the explosion took place told WFMZ he was standing outside when a man driving a gray pickup truck tossed something out the window and it exploded.
No injuries have been reported.
Bethlehem police and ATF are continuing their investigation.
Stay with Action News as we continue to follow this developing story.