Hawaii's electric utility company says its downed power lines started the first wildfire on Maui, but blamed county firefighters who declared the fire contained and left the scene before a second fire broke out in the area.

In a statement issued Sunday, Hawaiian Electric (HECO) alleges that fire department incompetence led to the destruction of Lahaina, not its own neglect.

The utility said that the first fire on the morning of Aug 8 "appears to have been caused by power lines that fell in high winds''.

It said, however, that the Maui County Fire Department reported it was "100 percent contained," left the scene and later declared it extinguished, only to have a second fire flare up in the same area.

HECO said the county's lawsuit accusing the utility's power lines of sparking the deadliest US wildfire in over a century is "factually and legally irresponsible".

"We were surprised and disappointed that the County of Maui rushed to court before completing its own investigation," Shelee Kimura, president and CEO of HECO, said in the statement.

HECO claimed it later went to the scene of the first fire to make repairs and ensured that the power lines were de-energized and the power in the area remained off. It said crews saw no fire, smoke or embers when making those repairs.

HECO's statement conflicts with accounts of residents who live near the Lahaina substation and were home for both blazes, as well as the findings of Maui officials, who allege in their lawsuit that it was the earlier fire that destroyed the community.

Richard Fried, a Honolulu attorney working as co-counsel on Maui County's lawsuit, said that if their power lines hadn't caused the initial fire, "this all would be moot".

"That's the biggest problem," Fried told The Associated Press on Monday. "They can dance around this all they want. But there's no explanation for that."

Mike Morgan, an Orlando, Florida, attorney who is on Maui to work on wildfire litigation for his firm, Morgan & Morgan, said he thinks Hawaiian Electric's statement was an attempt to shift liability and total responsibility.

"By taking responsibility for causing the first fire, then pointing the finger on a fire that started 75 yards away and saying, 'That's not our fault, we started it, but they should've put it out,' I'm not sure how that will hold up," Morgan, who manages complex litigation, told the AP. "It's also so premature because there are ongoing investigations."