31 workers have been rescued after an industrial tunnel collapsed in Wilmington, Los Angeles.

On Wednesday, July 9, the Los Angeles Police Department confirmed that 31 people had been rescued with no visible injuries.

“31 persons, all believed to be tunnel workers, have been safely removed from the tunnel alive without visible injury,” the update read. “None are missing.”

Officials stated that the collapse took place at an underground “horizontal excavation site about 5 to 6 miles south of the sole entry/rescue access portal.”

The tunnel had an 18-inch diameter and was being built  “for municipal wastewater management.”

Aerial footage from local television showed workers being lifted up through the tunnel’s entrance, per The Independent.

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Per the statement, preliminary reports found that the workers who had been trapped had to scramble over 12 to 15-foot tall piles of loose soil to get to the other side of the collapse, where their other coworkers were located. The workers were then transported in tunnel vehicles to the access point, which was “more than five miles distant.” The Independent notes that the rescused workers were then evaluated by paramedics.

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LAFD Interim Fire Chief Ronnie Villanueva said that four workers scrambled through debris in the tunnel, which will eventually carry wastewater, to help their 27 coworkers who had become trapped.

“Tonight, we were lucky,” Villanueva said, per NBC News. According to The Independent, more than 100 LAFD workers were assigned to the scene, including those who specialize in rescues from confined spaces.

Earlier in the rescue mission, the LAFD had released a statement asking media helicopters “to be no closer than one mile from the intersection of Figueroa Street and Lomita Boulevard,” due to the noise interfering with the rescue operation.”

Mayor Karen Bass, who arrived at the scene in Wilmington, thanked the first responders for their efforts after the rescue was complete.

“LAFD has just reported that all workers who were trapped in the tunnel in Wilmington are now out and accounted for,” she wrote on X alongside a video of her shaking hands with the firefighters. “I just spoke with many of the workers who were trapped. Thank you to all of our brave first responders who acted immediately. You are L.A.’s true heroes.”