A total of 42 illegal migrants, who were planning to cross the Aegean Sea to reach Greece, have been captured Friday by Turkish coast guard in the western provinces of Aydın and Izmir.

An operation was launched early Friday after a helicopter spotted a boat full of migrants in Aydın's Kuşadası district, the coast guard command said in a written statement.

The captured migrants were later identified as Syrian, Afghan, Iranian and German nationals.

Meanwhile, coast guard units in Izmir's Dikili district also launched an operation early Friday upon receiving tipoffs about a group of migrants trying to illegally reach Greece in a dinghy.

Some 40 illegal migrants of Syrian origin, including 10 women and 18 children, were captured during the operation.

Over the past years, thousands of people have made the short but dangerous journey across the Aegean in a bid to reach Greece, before continuing on to northern and western Europe.

Turkey's five Aegean provinces Çanakkale, Balıkesir, Izmir, Muğla and Aydın are the regions most frequently used by refugees leaving Turkey for the EU.

The EU-Turkey agreement reached on March 20, 2016, allows for the return of "irregular migrants" to Turkey from Greece, in exchange for Syrian refugees' relocation from Turkey to within the bloc.