SAN DIEGO -

A federal investigation was under way today into a recently completed, highly sophisticated tunnel found between San Diego and Tijuana.

Several federal agencies that compose the San Diego Tunnel Task Force uncovered the passageway, spokeswoman Lauren Mack of Immigration and Custom's
Enforcement told reporters late Wednesday.

According to Tijuana media, the tunnel's entrance is just south of the border fence west of the Otay Mesa Port of Entry.

It was not immediately clear whether the tunnel had ever been put in use for smuggling drugs or people prior to it being discovered by the task force.
U.S. authorities were expected to release more information later today.