LOS ALAMOS, N.M. (AP) -- Honking horns and waving to firefighters, residents of a New Mexico city threatened by a massive wildfire rolled back into Los Alamos nearly a week after flames forced an evacuation and the closure of a nearby major nuclear weapons laboratory.
Summer showers gave a boost to firefighters battling the blaze and provided authorities enough confidence Sunday to allow the 12,000 residents to return home.
"Thank you! Thank you! Thank you!" yelled Amy Riehl, an assistant manager at the Smith's grocery store, as she arrived to help keep the store open for returning residents.
"It's scary, but all of the resources here this time, they were ready. They did a magnificent job," said Michael Shields, his eyes tearing up as he returned to his apartment in the heart of the town.
The fire erupted June 26 when a tree fell onto powerlines, officials announced Sunday. Fueled by an exceptionally dry season in the Southwest and erratic winds, the fire has mushroomed to 189 square miles. It was 19 percent contained as of Sunday night.
Although the threat to the community and the Los Alamos National Laboratory has waned, the wildfire still menaced sites held sacred by American Indian tribes.
The blaze, the largest ever in New Mexico, reached the Santa Clara Pueblo's watershed in the canyon last week, damaging the area that the tribe considers its birthplace and scorching 20 square miles of tribal forest.
Fire operations chief Jerome Macdonald said it was within miles of the centuries-old Puye Cliff Dwellings, a national historic landmark.
Hundreds of firefighters were working to contain the fire as it burned through a canyon on the Santa Clara reservation and caused concern about other pueblos on the Pajarito Plateau.
Tribes were worried that cabins, pueblos and watersheds could be destroyed.
Los Alamos residents fled en masse last week as the fast-moving fire approached the city and the nation's premier nuclear research lab, located northwest of Santa Fe.
The town was last evacuated because of a devastating fire in 2000 that destroyed 200 homes and several businesses and damaged utilities and other county enterprises.
This time, residents returned to a town that is completely intact, although the fire scorched 63 homes west of town along with 37 outbuildings and other structures.
"We're confident that we'll be able to keep the fire out of the community," Los Alamos County Fire Chief Doug Tucker said. "We've done so far, and we'll continue to do so."
He added that's it's a bittersweet moment because of all the residents in surrounding areas that lost their homes.
Many lab employees returned to prepare operations and thousands of experiments for the scientists and technicians who were forced to evacuate. Among the work put on hold were experiments using two supercomputers and studies on extending the life of 1960s-era nuclear bombs.
Thunderstorms that dropped rain Sunday also brought wind that made the fire burn more aggressively in some areas but pushed the 121,000-acre fire back on itself in the north, said Brad Pitassi, a spokesman for the fire command.
The blaze remained in Los Alamos Canyon, which runs past the old Manhattan Project site and a 1940s-era dump site of low-level radioactive waste, as well as the site of a nuclear reactor that was demolished in 2003.
For Leo and Lorene Beckstead, their first stop in town was the grocery store as they prepared to heed officials' request that residents stay at home as crews worked on the fire surrounding the town on three sides.
"They did a great job. I think because of the Cerro Grande fire, they learned a lot," Leo Beckstead said, referring to the blaze in 2000.
Other residents turned back and left as soon as they got home.
"A lot of them are coming in, checking their houses and then leaving because the smoke is so bad," said Tucker. "They're turning around and leaving Los Alamos."
High humidity pushed the smoke down into towns and kept it close to the ground, Tucker said.