Two people have been killed after a police helicopter monitoring violent clashes between white supremacists and anti-fascists in Charlottesville, Virginia, crashed.
In a message on Twitter, Donald Trump said: "Deepest condolences to the families and fellow officers of the Virginia State Police who died today. You're all among the best this nation produces."
Fighting broke out between the two groups after far-right demonstrators gathered to protest against plans to remove a statue to Civil War Confederate general, Robert E Lee.
Some were dressed in paramilitary uniforms and carried assault rifles, while others were had shields, helmets and gas masks. At least one person was killed when a car drove into a group of anti-fascist activists.
Police said the pilot and a passenger had died in the police helicopter.
Officials said the crash was linked to the protests, but it was not immediately clear whether this was simply because the helicopter had been monitoring events on the ground or if there was any other kind of connection.
Local people told the Daily Progress newspaper that the helicopter had been hovering low over some houses before moving over an area of woodland, where it crashed near Birdwood Golf Course.