At least 700 people on board capsized boat off Greece

A boat carrying hundreds of migrants has capsized off the Greek island of Crete and a major rescue operation is underway, the Greek coastguard said Friday.

At least 700 migrants were believed to be on board a boat that capsized off the Greek island of Crete Friday, with hundreds still missing, the International Organization for Migration said.

"Over 250 people have been rescued from a shipwreck off Crete which is believed to have left Africa with at least 700 migrants on board," the organisation said in a statement.