MEXICAN AUTHORITIES IN the border city of Tijuana found a tunnel designed to smuggle people without documentation into the United States, the government said this week.

Three suspected people-traffickers were arrested, a statement from the National Migration Institute said.

The alleged smugglers were turned over to the Federal Public Ministry for further investigations.

Although no details of the size of the tunnel were given, two ‘safe houses’ were discovered. The first was used to gather migrants before they moved to the second house, where the tunnel began.

Police acted on an anonymous tip about a possible kidnapping of migrants held in a residential area of Tijuana, which borders California.

Tunnels of varying degrees of size and sophistication have been found in Tijuana – about 80 since 2008. Authorities say some were used to smuggle both people and illegal drugs into the United States.

In one of the most elaborate ones, found in October of last year, police came across eight tons of marijuana and 148 kilos of cocaine.

It was 200 metres long and was equipped with electricity and ventilation, officials have said.

- © AFP, 2014 with additional reporting by Sinéad O’Carroll

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