Greek authorities said Wednesday 91 migrants landed on Gavdos, a Mediterranean island that has become a gateway to the EU for African asylum seekers in recent months.

"The Crete port authorities were informed at dawn on Wednesday of the presence of a group of 91 migrants on Gavdos," the coastguard said in a statement.

More than 60 of the migrants remained in a temporary camp in Gavdos while 28 others were transferred to a shelter on Crete, the coastguard added.

Greek police said they also arrested a 23-year-old who is believed to be the suspected people-smuggler.

No details were provided of where the migrants were from.

According to local media, over 250 migrants have landed on Gavdos since last weekend.

Gavdos, a 30-square-kilometre island with a population of 50, has seen a substantial increase in the number of migrants arriving in recent months, mainly from the Libyan port city of Tobruk -- 170 nautical miles away.

Since the start of the year, around 1,000 asylum seekers have arrived at Gavdos including a number of unaccompanied minors, Greece's migration ministry said.

Local authorities in Gavdos recently sounded the alarm about the lack of adequate resources on the island to help migrants, most of whom are from African countries.

"We are under pressure from migratory flows in the south of Crete" and "the capacity of the centres for minors have reached their limits," Sofia Voultepsi, secretary of state at the migration ministry, said recently.

She pointed out that Gavdos and Crete have now become a destination for migrants the same way the Italian island Lampedusa used to be.

Greece has stepped up patrols also in the Aegean Sea with the help of the European Union's border protection agency Frontex.

In June, a dilapidated boat capsized and sank off Pylos in the Peloponnese, drowning 82 people, while hundreds were reported missing.

Forty of the survivors have filed a group lawsuit against Greek authorities alleging they failed to take appropriate action before the boat sank.