Law enforcement officials on both sides of the San Diego-Tijuana border are searching for a tunnel that may run beneath the border fence.
Immigration and Customs Enforcement spokeswoman Lauren Mack says the search began around 4:30 p.m. Monday. She says it is a joint investigation with ICE agents and the Mexican Army working together.
Mack says a tip sent authorities into action, though she would not specify if the information came from someone in the U.S. or Mexico.
She says ICE agents will work until dark to find an exit on the U.S. side. Then, they’ll secure the area and begin again in the morning.
She says agents could bring in a back hoe to try to dig up the tunnel, if they can’t find the exit searching above ground.
Authorities have unearthed more than 100 tunnels along the U.S. Mexico border since the 1990s. The vast majority were rudimentary passageways.