JUNEAU -- A grand jury in Juneau has indicted two people in connection with an arson fire at a park.

The Juneau Empire says 23-year-old Ryan Martin and 18-year-old Ashley Johnston are facing third-degree arson charges. They are accused of intentionally damaging a motor vehicle by starting a fire or causing an explosion.

If convicted, they could face sentences of up to five years in prison and a $50,000 fine.

Prosecutors have said Johnson and Martin and another man were caught on video surveillance footage in the park on June 19. The grand jury did not indict the third person.

Investigators say the arson caused about $20,000 in damage as it scorched materials being used to replace the tarp football field, including a John Deere tractor and a spreader trailer.