State investigators have joined the effort to determine what caused a large fire that destroyed two homes this week on Dewees Island.

Dewees Fire Chief Randy Snipes said he didn’t think the blaze, which occurred around 9 p.m. Wednesday at a home being built on the exclusive island, was set intentionally. But the State Law Enforcement Division’s resources were sought because the island’s fire department is so small.

SLED spokeswoman Kathryn Richardson confirmed Friday that the state was assisting in the investigation, but she would not comment further.

The inferno prompted a massive response by resident volunteers and professional firefighters from surrounding communities. It took the crew more than three hours to get the blaze under control, according to islanders.

It started in a house that was being construction on the 65-home island and quickly spread to a neighboring structure that also wasn’t occupied. Nobody was hurt.