ANKARA, Turkey — A rubber boat carrying migrants capsized in the Aegean Sea on Wednesday following a high-speed chase by the coast guard, killing 18 migrants, officials said. At least 21 other migrants were rescued.

The Turkish Coast Guard Command said the boat carrying dozens of migrants ignored repeated warnings to stop and attempted to flee at high speed. The boat began to take on water in the rough seas and eventually capsized.

The sinking occurred off the coastal city of Bodrum, a popular Turkish vacation destination.

Rescue teams, supported by a helicopter dispatched from the nearby city of Izmir, pulled 21 survivors from the water and recovered 18 bodies, the Coast Guard said.

Rescue teams were continuing to look for any possible remaining victims.

The nationalities of those on board the boat were not immediately known.

The island of Kos lies some 20 kilometers (13 miles) from Bodrum. Other nearby islands include Kalymnos, Leros, and Symi.

Greece is one of the main entry points into the European Union for people fleeing conflict and poverty in the Middle East, Africa and Asia, with many making the short but often treacherous journey from the Turkish coast to nearby Greek islands in small boats. Many are unseaworthy, or set out in bad weather, and fatal accidents have been common.