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Marijuana, looking for a tunnel.REUTERS/Alessandro Bianchi

For the first time in criminal history, authorities say Mexican drug traffickers purchased a house in California to serve as the import end of a smuggling tunnel they dug across the border.

Four people were arrested following a raid on the tunnel beneath a three-bedroom beige stucco house in Calexico, California,. The house is located a couple of city blocks north of the international line, authorities said.

The front room had a hole in the floor that led to a shaft into a tunnel with a rail system, lighting and electricity, authorities said. Contractors who built the house were told to leave space for a floor safe.

The house was scouted out by drug traffickers in 2015 and they purchased it then for $240,000 (£170,000). It's located in a quiet community of single-family homes.

"This is a peaceful neighborhood. You just don't hear about stuff like this here," neighbor Juan Urrea told CNN. "Crazy. Just crazy."

Another resident said the community was happy because the house was newly built and neighbors thought it would be good for property values. Then "we wake up with a huge, big bang. Helicopter. Police. I got out of my house," she said.

The tunnel entrance was on the Mexican side of the border inside a restaurant in Mexicali, said US Immigration and Customs Enforcement officials. Authorities confiscated 1,530 pounds (694kg) of marijuana, with a street value of nearly $6m (£4.25), in the raid on the home.

Two men were arrested in Calexico, and a mother-daughter team were held in Arizona. The women purchased the land where the American side of the tunnel was built, said authorities. All four were charged with various drug trafficking and money laundering crimes.

"For the builders, the financiers and the operators of these sophisticated tunnels, there is no light at the end of the tunnel. We will seize your drugs and your tunnel before you even have a chance to use it," said US Attorney Laura Duffy of Southern California.