Gun seller takes stand in Trump assassination attempt trial with key testimony about rifle purchase

Also scheduled are Lazaro and Samuel Plata, whose testimony will be aided by two Spanish-English translators in the courtroom.

FBI experts also testified that Routh's DNA was strongly linked to the rifle grip, a bag, a glove and other items prosecutors say were found in the alleged sniper's nest. Trump-appointed Judge Aileen Cannon kept a tight rein on the pace of testimony, pressing prosecutors to shorten questioning and reminding Routh - who is representing himself - to stop interrupting.

With prosecutors expected to rest their case by the end of the week, Wednesday's testimony could prove pivotal as jurors weigh the government's evidence against the self-represented defendant who will bring his witnesses forward beginning next week.