ROME — A Spanish humanitarian group says it has rescued three migrant brothers who set out from Libya in a rubber dinghy to seek leukemia treatment for one of them.

Riccardo Gatti of the aid group Proactiva Open Arms told Italy's RAI state TV on Sunday night the group's rescue ship spotted the dinghy by chance in the Mediterranean Sea between Libya and Sicily.

Gatti says the little boat carried only three people, one of them a boy with an IV line attached to his body.

He says the brothers told Proactiva's crew that doctors at a Libyan hospital had said they couldn't save the 13-year-old sibling's life, so they bought the dinghy and departed in search of a cure.

The three brothers, whose nationalities weren't revealed, were being taken to Sicily.