LA MORA, Mexico (Reuters) - Two months after tragedy struck, beefed-up security has helped calm the holdout residents of a tight-knit community of U.S.-Mexican families of Mormon origin. But with only a few families staying put, at least one village is being hollowed out.

The gangland ambush by cartel gunmen in November on a dusty road in northern Mexico left three mothers and six children dead, their charred vehicles riddled with bullets, and a once-strong faith deeply shaken in the picturesque hamlets the families have called home for generations.

“La Mora will never be the same,” said 27-year-old holdout Kendra Miller, whose brother Howard lost his wife Rhonita and their four children in the attack.

“There are families that will come back to visit, but they’re not going to live here again because they don’t feel safe,” she said.

Today, roads in and around La Mora are patrolled by hundreds of heavily-armed soldiers, helicopters buzzing overhead.

The showy security presence, set against a backdrop of many already-vacated homes, comes as President Andres Manuel Lopez Obrador is set to make his first visit to the grieving community on Sunday.

The leftist president who has pursued a less confrontational security policy is nonetheless set to speak at a fortified event center, erected in the past few days for his visit.

Dozens of armed patrols could be seen on Saturday as nearby homes were searched.

Some locals complain that the police presence before November’s attack was almost non-existent, but since then army soldiers and National Guard troops have flooded in, along with FBI and Mexican investigators.

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Beyond the sympathetic hand extended to the victims’ families, Lopez Obrador’s one-year-old government has struggled to tame rampant drug violence nationwide as homicides are at a record high and several spectacular security setbacks have played out on his watch.

Nearly all of the family members are both U.S. and Mexican citizens, meaning they can easily travel, or relocate, between both countries.

The large families that have populated this part of northern Mexico, nestled among rolling hills and gurgling rivers, stem from breakaway Mormon communities that began fleeing the United States more than a century ago in search of safe havens for their polygamist beliefs.

They built ranch-style homes with orchards where the young children of growing families could ride their bikes and play all day outside.

Like Miller, many wax nostalgic about care-free childhoods, even if their own kids might be raised elsewhere.

“I was set to get married one week after the massacre,” she said, “and now my fiance wants us to live in the United States.”

On an impromptu tour of the area, Miller points out the many homes that sit eerily empty, once tidy gardens overrun with weeds.

Other family members describe how kids suffer from recurring nightmares, and those relatives who have left fear coming back.

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‘BAD THINGS HAPPEN’

The Mexican government has arrested seven suspects to date as part of the investigation into the massacre, but the reasons behind the killings remain shrouded in mystery.

Officials have suggested the attack may have been linked to a turf battle between two rival cartels known to fight over lucrative smuggling routes between Sonora and Chihuahua states, which both border the United States.

Despite the heightened security presence on the ground, some family members returning to the area ahead of Lopez Obrador’s visit opted to travel in small planes instead.

Others have been provided with armed escorts from Mexican security forces.

While they are a distinct minority, there are those among the families who argue against leaving.

“I’m not going anywhere,” said Mateo Langford, whose sister was killed in the attack.

“Bad things happen in every corner of the world, including in the United States. We just can’t run away,” he said.

As he sorted pecans from last year’s harvest, Mateo’s brother Steve Langford, whose sister Christine was killed, said he will stay put as well.

He said his immediate plans are to help his cousin David with the harvest, and try to convince him to stay too.

David lost his wife Dawna and two of their children in the attack. Another remains hospitalized with a gun shot wound to the jaw.

“I’ll never leave here,” said Langford.