GRAND MANAN, New Brunswick – A two-person scuffle that turned into a 40-person riot Saturday morning and led to arson on this small island off the Maine coast is still under investigation, Royal Canadian Mounted Police said Tuesday.

Police know little about what caused the melee or about the two groups of people involved in the riot, but they say an arsonist set a house ablaze, destroying the building. The fire caused no injuries, although some people lived in the house, Cpl. Mark Gallagher said. Police will find whoever torched the house, he added.

“There is no statute of limitations on an arson,” Gallagher said.

Police have had trouble gathering clues, because residents have not come forward with information.

“If people are willing to participate, we can resolve the problem,” Gallagher said.

More information needs to be gathered before anyone can be charged.

“We are trying to find out the root cause,” Gallagher said. He and a couple of other officers were sent to the island to quell the riot and disperse the crowd.

Gallagher couldn’t confirm reports of shots being fired, but he said a damaged car may have been the result of gunfire.

The arson and the riot are highly unusual, he said.

“It’s out of character for the citizens [of Grand Manan],” the corporal said.