Border Patrol agents found a cross-border tunnel in Otay Mesa early Saturday after dozens of people emerged from it, federal authorities said.

Agents caught four Mexican men and three women, and 23 Chinese nationals, including two women. They apparently had just been smuggled into the United States through the tunnel, Customs and Border Protection spokesman Ralph DeSio said.

The agents were in the area of the border and Drucker Lane about 1:15 a.m. when they saw a large number of men and women on the street. They started running when agents approached them, Border Patrol Agent Eduardo Olmos said.

Those who were detained were taken to the Border Patrol station in Chula Vista to be questioned. The San Diego Tunnel Task Force led by U.S Immigration and Customs Enforcement Homeland Security Investigations is handling the investigation and working with Mexican authorities.


A red dot shows the tunnel location on Drucker Lane north of La Media Road and the Mexican border. (U.S. Customs and Border Protection)

Some of the people tried to get back to the tunnel, leading agents to discover its existence, Olmos said. He did not know if some people succeeded in getting back to Mexico.

The tunnel appeared as a hole in the ground in a weedy area north of a secondary border fence, not far from the Otay Mesa Port of Entry. There was a ladder inside. It may be an extension of an incomplete tunnel found previously and seized by Mexican authorities, DeSio said.