Oct 16 (Reuters) - U.S. President Donald Trump said in a social media post on Thursday that if militant group Hamas continued to people kill people in Gaza "we will have no choice but to go in and kill them." (Reporting by Costas Pitas; Editing by Doina Chiacu) (The article has been published through a syndicated feed. Except for the headline, the content has been published verbatim. Liability lies with original publisher.)