Nogales city officials said they believe a sewage flood was caused by a possible drug tunnel from Sonora to Arizona.
The cross-border sewer line carries more than 10 million gallons of raw sewage from Mexico and the United States every day.
“We haven't found the drugs yet, but the sewer line is totally blocked,” Deputy City Manager John Kissinger said.
Kissinger said it appeared that smugglers had dug a tunnel from under a house on Morley Avenue in an attempt to extract drugs being brought across the border through the sewer line, but damaged the pipe in the process.
To remove the drugs, or whatever is blocking the line, Kissinger said that the avenue need to be torn up.
Authorities also said that recent smuggling attempts have disrupted the flow of sewage through city lines.