TAIPEI, Nov 28 (Reuters) - A Panama-registered ship sank off the northeastern tip of Taiwan due to rough weather as Typhoon Mitag hit the area, leaving almost 30 people missing, an official from Taiwan's Coast Guard Administration said on Wednesday. The coast guard managed to rescue one man, who could be Indonesian, after it received the cargo ship's call for help at 0650 GMT on Tuesday, the official said. "From yesterday to today, we haven't found anyone else, but the coast guard has not given up hope yet. However, because of the strong winds, the rescue effort has been difficult," the official told Reuters by telephone. Typhoon Mitag, which hit the region earlier this week, has already killed around 19 after more people were drowned by flooding in the northern Philippines. Earlier in the day, the Philippine coast guard said two Chinese fishing boats sank in rough seas caused by another typhoon off the Philippines and at least 12 people were missing. (Reporting by Ralph Jennings and Christine Lu; Writing by Lee Chyen Yee; Editing by Jerry Norton)