Oct 22 (Reuters) - An earthquake of magnitude 7 struck China's southwestern region of Tibet at around 10:33 p.m. (1433 GMT) on Thursday, killing 16 people and injuring 32 others, state news agency Xinhua reported, citing Nagqu City's emergency management bureau. As of 2:25 a.m. on Friday, 11 of the injured were in serious condition while 21 sustained minor injuries, Xinhua reported. L...