A home owner discovered six soda bottle bombs scattered across a walking path in Waldorf on Tuesday.
Sabrina Maxwell alerted the police after hearing a series of loud explosions behind her fenced-in yard in a townhouse community near Waldorf Market Place.
The State Fire Marshal's Bomb Squad rendered safe two chemical bombs which hadn't detonated.
Soda bottle bombs are homemade chemical reactions bombs and can be made in a variety of ways. They are considered dangerous.
Official are planning a follow-up investigation.
In May, authorities discovered several homemade bombs in Pomfret in Charles County.