Kurt Volker, a former envoy to Ukraine, testified before the House Intelligence Committee on Tuesday afternoon that he should have realized President Trump’s true motives in demanding that Ukraine investigate Burisma, a natural gas company that employed former vice president Joe Biden’s son Hunter.

Volker testified alongside Tim Morrison, a former senior National Security Council official, as Democrats press forward with their impeachment inquiry into President Trump. Their remarks came after Lt. Col. Alexander Vindman, another NSC official, and Jennifer Williams, an adviser to Vice President Pence, testified earlier Tuesday.

Vindman, a key witness in the impeachment inquiry, said he was alarmed by Trump’s July call with Ukrainian President Volodymyr Zelensky, which Vindman called “improper.” Democrats are seeking to prove that Trump leveraged military aid and a White House meeting in exchange for investigations of the Bidens and other Democrats.

●Vindman reveals in testimony that he told an intelligence official about Trump’s call with the Ukrainian leader.

●The House is investigating whether Trump lied to then-special counsel Robert S. Mueller III, its general counsel told a federal appeals court.

●Attacking witnesses is Trump’s core defense strategy in fighting impeachment.