COLEVILLE, Calif. (AP) - Most families returned to a military housing complex outside a remote U.S. Marine training base in Northern California on Sunday, two days after a propane gas explosion that killed a Marine's wife and critically burned two other people.

A total of 38 families were displaced from the military neighborhood in the Mono County town of Coleville that serves the U.S. Marine Corps Mountain Warfare Training Center, where Marines train for mountain operations.

Twenty families had returned by late Sunday, and 18 remained displaced, Marine Corps spokesman Capt. Nicholas Mannweiler said.

The explosion destroyed only one house at the center of the blast, but left 11 uninhabitable, Mannweiler said.

But the complex has exactly 11 vacant housing units that those families can move into, he said.

The remaining seven families will return based on their own needs and timing.

The woman killed in the blast was Lori Hardin of Hudson, Iowa, the 31-year-old wife of Gunnery Sgt. Greg G. Hardin, military officials said. The Marine Corps public works planner from Tuolumne, Calif., and the couple's two children were not hurt in the Friday night explosion.

Two other blast victims, a Navy corpsman and his wife, were flown to hospitals with serious injuries including third-degree burns.

The corpsman was treated at Renown Regional Medical Center in Reno, Nev., and was released Saturday. His wife remained in critical condition at the University of California, Davis Medical Center, though her condition was improving, Mannweiler said.

The couple has asked that their names not be released, Mannweiler said.

The explosion was related to the housing area's propane distribution system, and was not associated with activities at the Marine base, which is about 30 miles away, according to the Marine Corps.

After safety inspections Saturday night, inspectors began testing the propane distribution system house-by-house for leaks or any other signs of trouble and ensuring that gas-powered appliances are re-lit and functioning properly. Families in homes found to have minimal damage began moving back in Sunday, and other families will be moved back in one by one throughout the coming week, Mannweiler said.

"We have to inspect everything to make sure we're not jeopardizing our families," he said.

Other people suffered superficial cuts and bruises in the explosion, which was being investigated with help from the California Department of Forestry and Fire Protection.

Located at an altitude of about 9,000 feet in the Sierra Nevada mountains near the Nevada border, the Mountain Warfare Training Center is one of the Marines' most remote posts, used for training for cold and mountainous areas.

It's has about 160 marines and 300 civilian employees.

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