Hillary Clinton went off-script in several key portions of her speech Thursday, which attacked Donald Trump over what she called his “divisive” language and “steady stream of bigotry,” amid an escalation in the rhetoric between the two.

Mr. Trump, for his part, has disavowed racist supporters and says Mrs. Clinton is the “bigot” in the race due to her policies.

In her ad-libbed moments, Mrs. Clinton added praise of federal Judge Gonzalo Curiel, whom Mr. Trump had criticized as biased in his handling of a Trump University suit; further criticized fringe conspiracy theories; and expanded on her outreach to Republican voters.

Here's a look at these moments.