July 10 (UPI) -- At least three crew members were killed and an unknown number of mostly Filipino seamen were missing at sea or being held hostage Thursday after Houthi rebels attacked and sank a Greek bulk carrier ship in the Red Sea off the Yemeni port city of Al Hudaydah. Operation Aspides, the European Union freedom of navigation naval mission in the Red Sea, said that it had pulled four more men from the sea overnight. "During the night, three additional crew members from the MV Eternity C