BARCELONA, Spain (AP) — Spain’s Maritime Rescue Service says it has rescued three stowaways traveling on a ship’s rudder in the Canary Islands after the vessel sailed there from Nigeria.

The men, found on the Alithini II oil tanker at the Las Palmas port, appeared to have symptoms of dehydration and hypothermia and were transferred to hospitals on the island for medical attention, Spain’s Salvamento Marítimo said.

According to the MarineTraffic website which tracks ships, the Malta-flagged vessel left Lagos, Nigeria on Nov. 17 and arrived in Las Palmas Monday.

Though extremely dangerous, it is not the first time stowaways have been found traveling on the rudder of commercial ships to the Canary Islands. Last year, a 14-year-old Nigerian boy was interviewed by Spain’s El País newspaper after surviving two weeks on a ship’s rudder. He had also departed from Lagos.