Someone called 911 at 2:30 p.m. after finding the two devices inside City Park, according to Pacific Police.
Officers arrived at the park and found the devices, which looked like metallic pipes with end caps and fuses. Police then called in the Federal Way Bomb Squad for assistance.
Using a robot, the bomb techs "neutralized" the devices.
Police reopened the park and nearby roads at 4 p.m.
The investigation is ongoing.