The Border Patrol on Wednesday detained 20 undocumented Mexican migrants on a beach in San Diego after they arrived on the coast in a small boat.

Authorities said that the immigrants arrived on a beach in Carlsbad, a neighborhood in northern San Diego, but were intercepted there shortly thereafter.

Border Patrol agents decided to search the area after one of them saw the empty boat and noticed footprints in the sand which ultimately led them to 18 of the migrants.

The first and larger group of Mexicans was discovered among the bushes growing at the side of a road near the beach. Their clothing was still wet and some of them were wearing flotation devices, Border Patrol spokesman Michael Jimenez said.

After intercepting this group of migrants, agents shortly thereafter found two others who had arrived with the others in the vicinity.

Jimenez said that all the people detained are Mexicans and they range in age from 17 to 50. Authorities found no drugs or contraband among their possessions.

The increase in border security has forced migrant traffickers to diversify their strategies for crossing from Mexico into the United States, and the sea has proven to be an efficient and attractive option that involves less work than digging cross-border tunnels or guiding migrants through the inhospitable Arizona desert.

The new migrant-trafficking corridor in Pacific coastal waters extends from the beaches of Baja California in Mexico north to San Diego County up to where the Camp Pendleton military base is located and where coastal security is substantially increased.

The Border Patrol has reported that due to recently stepped-up maritime security it has registered a decrease for the first time in the number of sea crossings in the San Diego area. EFE