ATHENS — Greek authorities say another sailboat carrying dozens of migrants arrived Thursday at Kythera, the third in just under two days to make it to the southern island that isn’t on the usual route for asylum-seekers trying to reach the European Union.

Greece’s coast guard said 67 people had been on board the sailing catamaran that arrived in a harbor on Kythera’s western coast, and that all had disembarked themselves. Their nationalities and where they had set sail from weren’t immediately known.

In all, 237 migrants arrived on the island between the early hours of Wednesday and around mid-day Thursday. Of the two other sailboats that reached the island Wednesday, the first ran aground on the island’s southern coast with 97 people on board — 93 from Afghanistan, three from Turkey and one from Pakistan, authorities said.

The passengers made it to shore themselves, and no one was reported injured or missing. The coast guard said Thursday that the boat had set sail from the Cesme area in Turkey and the group included 55 children. The three Turkish nationals on board, ages 30, 29 and 17, were arrested as suspected migrant-smugglers.

Hours later, another vessel carrying 73 people — 62 Iraqis, nine Iranians and two Russians — arrived in a small southern harbor of Kythera, escorted by the coast guard, authorities said. Those on board included 21 minors and six women. The coast guard said Thursday that the two Russian nationals on board were arrested as suspected smugglers.

Located off the southern tip of the Peloponnese, Kythera isn’t a target destination for the thousands of people fleeing conflict and poverty in the Middle East, Asia and Africa. Most attempting to make it into the European Union cross from the Turkish coast to nearby Greece’s eastern Aegean islands.

But with Greek authorities increasing patrols in the area and facing persistent reports of summarily deporting new arrivals back to Turkey without allowing them to apply for asylum, more people are attempting a much longer and more dangerous route directly to Italy.

Greek authorities deny they carry out illegal summary deportations of asylum-seekers.