Twelve Cuban migrants were detained Tuesday in the eastern Dominican Republic when they were getting ready to clandestinely set sail for the U.S. commonwealth of Puerto Rico, the Dominican navy said.

The Cubans - three women and nine men - were arrested on the beach in the municipality of Juan Dolio, 70 kilometers (43 miles) each of the Dominican capital.

The migrants were going to set sail on board a boat approximately 17 feet in length, according to the navy communique.

Also found on the beach were an outboard motor, two containers of gasoline, six life jackets, a canvas sail, two oars, an automobile and three cell phones, the navy added.

The navy also said that the arrests were made after an "arduous" process of gathering intelligence jointly with police and prosecutors.

Among the detainees were two Cubans identified by Dominican intelligence as the organizers of the voyage and whom the local authorities had been following for several months as part of an investigation of a migrant-trafficking ring.

Navy units were continuing to search the area.

The Dominican Republic is separated from Puerto Rico by the Mona Passage, a channel 100 kilometers (62 miles) wide. The journey is a dangerous one and many migrants die trying to reach U.S. territory.

The Dominican navy has intercepted more than 200 would-be migrants so far this year. EFE