WASHINGTON (REUTERS) - The United States holds North Korea accountable for its treatment of US student Otto Warmbier and wants three other US citizens detained by Pyongyang to be freed as soon as possible, the US State Department said on Tuesday (June 20).

"We hold North Korea accountable for Otto Warmbier's unjust imprisonment," State Department spokeswoman Heather Nauert told a news briefing.

Warmbier died on Monday days after being returned from North Korea in a coma after being imprisoned for 17 months.

"We want to see three other Americans who were unjustly detained brought home as soon as possible," Nauert said.