A Sunday morning fire that sent flames bursting through the roof of a River Road home is being investigated as a possible arson, the St. George Fire Department said.

The fire, which broke out shortly before 3 a.m. at the house on 10437 River Road south of Gardere Lane, “was suspicious in nature and is being investigated as a potential case of arson,” said Eldon Ledoux, a spokesman for the St. George Fire Department.

The home, which was undergoing renovations, was vacant at the time of the fire.

The blaze could be seen from Burbank Drive and Bluebonnet Boulevard, Ledoux said. About 50 percent of the house was heavily damaged in the fire.

Because the fire is under investigation, Ledoux said, no further details about the possible causes will be released at this time.