(Reuters) -Twitter Inc and Facebook Inc on Wednesday temporarily locked the accounts of U.S. President Donald Trump, as tech giants scrambled to crack down on his baseless claims about the U.S. presidential elections amid riots in the capital. Twitter hid and required the removal of three of Trump's tweets "as a result of the unprecedented and ongoing violent situation in Washington, D.C.," after pro-Trump protesters stormed the U.S. Capitol in an attempt to force Congress to block the appointment of President-elect Joe Biden. One woman was shot and killed inside the Capitol building in the chaos.