A pipe bomb exploded Saturday morning before a 5k charity run in honor of the U.S. Marines in Seaside Park, N.J., according to the Associated Press.
Local authorities said no injuries were reported.
The bomb was located in a plastic trash can and was apparently timed to explode during the race. However, the start of the charity run was delayed after officials spotted an unattended backpack nearby.
Authorities are investigating at least one more potential explosive device and are urging the public to stay clear of the area.
"There were multiple devices wired together. The one went off and the others did not," said Ocean County Prosecutor's spokesman Al Della Fave in an interview with CNN.
"Ive been told [there were] two to three additional devices."
He added that if the blast happened minutes later "there would have been a good number of people running past that explosive device."
Two pressure cooker bombs exploded near the finish line of the Boston Marathon in April 2013, killing three and injuring more than 250.
Updated at 2:25 p.m.