Fifteen migrants died after their boat collided with a coast guard vessel, capsized and sank off the Greek island of Chios in the Aegean Sea late on Tuesday, the Greek coast guard said, in one of Greece’s worst shipwrecks in years.

At least 14 migrants have died after a speedboat carrying them collided with a Hellenic Coast Guard vessel off the coast of the island of Chios late on Tuesday.

The bodies of 14 people — 11 men and three women — were recovered from the sea, the coast guard said, while another 25 migrants, including about 11 children, were rescued and transported to a hospital...