ISTANBUL, June 17 (Xinhua) -- Eight illegal migrants were killed while another went missing on Monday when their boat sank off Turkey's Aegean coast.

The rescue teams have pulled out eight bodies from the sunken boat at a depth of about 32 meters, the Turkish coast guard said in an updated statement posted on its website, as it reported earlier that 31 were rescued and nine others were missing.

The rescue operation is continuing to find the missing refugee, the statement noted.

It said the inflatable boat carrying a total of 40 refugees capsized near the Bodrum district in the southwestern province of Mugla.

The Aegean Sea was once the main route for migrants fleeing into Europe via Turkey. A deal signed between Turkey and the European Union in March 2016 has helped reduce the flow of illegal migration.

Since this year, a total of 10,855 migrants have attempted to reach Greek islands via Turkey, slightly down from 11,682 over the same period in 2018, according to figures released by the Turkish coast guard.