(KRON) -- Police in Petaluma are investigating a suspected arson that destroyed a portable toilet and damaged property belonging to the Petaluma Youth Soccer League early Monday morning. Police and Petaluma Fire Department crews responded to the soccer field at Lucchesi Park at around 4:45 a.m. to find a portable toilet consumed in flames. A nearby shipping container, which contained Petaluma Youth Soccer League property, was being threatened by the fire, police said. Some of the youth league’s shipping container contents were damaged, authorities said. Petaluma police and fire departments are conducting a joint arson investigation “relying on Petaluma FD’s experience with fire science and Petaluma PD’s familiarity with the crime scene investigation and familiarity with preparing investigations for prosecution in the Sonoma County Courts,” officials said. Air quality advisory issued for Novato due to landfill fire Suspected evidence was located at the scene, police said. Anyone with information is asked to contact the Petaluma Police Department at (707)-778-4372.