WASHINGTON — Independence Day is still over a month away, but chances are the sound of fireworks will be resonating through neighborhoods.

And if those fireworks make a boom, they’re illegal.

Residents in Riverdale, Maryland were surprised to hear an explosion dangerously close to their front door recently.

Surveillance video showed two young men lighting what appeared to be M-80 fireworks on the house’s front porch.

The explosion broke glass and melted siding near the door. Nobody was injured.

Prince George’s County Fire spokesman Mark Brady told NBC Washington the fire marshal’s office is investigating.

All fireworks are illegal, including sparklers, in Prince George’s and Montgomery Counties, Alexandria, and the city of Falls Church.

In Fairfax, Arlington, and  Prince William Counties, cherry bombs, skyrockets and fireworks that spark higher than 12 feet are banned. Sparklers are allowed.

In the District of Columbia, sparklers that are more than 20 inches long are illegal.

In Loudoun County, fireworks that move along the ground are not allowed.