The two migrants were picked up in Spain's Bay of Algeciras after crossing from Morocco on the large rubber tire. More than 750 people have died this year while making the sea journey to Spain.
Spain's coast guard on Saturday said it had rescued two young migrants who crossed the Strait of Gibraltar on a truck tire.
The pair were saved following "a call from Morocco to the Spanish sea rescue center warning that two minors were floating on a lorry tire in the Bay of Algeciras," a coast guard spokesman said.
"We mobilized a rescue vessel and warned all the boats in the area. A ferry called us to say that they had spotted them," he added.
The two minors were then taken aboard a coast guard vessel.
The migrants, whose age and nationality were not known, were taken to the Port of Algeciras.
The Strait of Gibraltar lies between Spain and Morocco and is just 14 kilometers (8 miles) wide at its narrowest point.
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Over the past year, the narrow strait that separates the Mediterranean from the Atlantic has seen a substantial rise in migrant crossings, due to the closure of other routes, including from Libya to Italy's Lampedusa island.
Increasing numbers of Moroccans and sub-Saharan migrants have been seeking to enter Spain, either by sea or by smuggling themselves into the Spanish enclaves of Ceuta and Melilla, which are in Morocco and the only European territories on the African continent.
Spain has become the main entry point for migrants to Europe, with more than 57,000 arrivals in 2018, according to the United Nations. Nearly 750 people have died or gone missing trying to cross from Africa to Spanish shores.
mm/jm (AFP, AP)