U.S. diplomat: Trump linked Ukraine aid to demand for probe

Ambassador William Taylor is escorted by U.S. Capitol Police as he arrives to testify before House committees as part of the Democrats' impeachment investigation of President Donald Trump, at the Capitol in Washington, Tuesday, Oct. 22, 2019. (AP Photo/J. Scott Applewhite)

WASHINGTON — A top U.S. diplomat testified Tuesday that President Donald Trump was holding back military aid for Ukraine unless the country agreed to investigate Democrats and a company linked to Joe Biden’s family, providing lawmakers with a detailed new account of the quid pro quo central to the impeachment probe.