An incomplete smuggling tunnel was discovered by authorities at the Arizona-Mexico border — the 126th underground pathway found by border agents in that area since 1990, officials said.

US Customs and Border Protection agents, along with Mexican authorities, located the tunnel that originated at a drainage facility in Nogales, Mexico, and extended 30 feet into Nogales, Arizona, CBP said in a press release.

Described by authorities as a “rudimentary” tunnel, the hand-dug pathway had no shoring, ventilation or lighting. Its depth was about 20-feet.

“U.S. authorities will continuously monitor the area until they remediate the tunnel,” CBP said in the release.

Last month, the federal agency reported finding the longest known Southwest drug-smuggling tunnel into the US at the California-Mexico border.

That tunnel, equipped with rail-cart and ventilation systems, was more than 4,300 feet long, extending from Tijuana, Mexico to a San Diego neighborhood.