The three Nigerian stowaways found on an oil tanker’s rudder after an 11-day ocean voyage from Lagos to Las Palmas in the Canary Islands are seeking asylum in Spain, officials have said.

The three men were picked up on Monday by Spain’s Maritime Rescue Service from the rudder of the Alithini II ship and transferred to two hospitals on the island of Gran Canaria with symptoms of dehydration and hypothermia.

One of them remains in hospital while the other two have been released, Spanish authorities said.

According to Spanish law, unless the stowaways seek asylum, or are minors, the ship owner or agent is responsible for returning them to their point of departure – in this case, Lagos. Given that the men are now seeking asylum, the ship is free to leave port again.

The asylum seekers’ identities and their motives for leaving Nigeria and hiding on the ship’s rudder have not been made public.

Earlier on Wednesday, the human rights organisation Walking Borders issued a statement demanding that the Spanish government should halt their potential return to Nigeria and calling for their cases to be assessed individually.

The statement was issued following reports by Spanish authorities that two of the men had been returned to the vessel for a potential voyage back to Nigeria.

The non-governmental organisation advocated that they should be placed into the government’s humanitarian program for migrants so they could recover from their ordeal and possibly seek asylum.

Spain’s Maritime Rescue Service shared a poignant photo that went viral this week showing the three men sitting precariously on top of the rudder with their feet only a few inches from the water’s surface under the ship’s massive hull.

According to the MarineTraffic tracking website, the Malta-flagged vessel left Lagos on November 17 and arrived in Las Palmas on Monday.

The distance between the ports is roughly 2,800 miles.