From Washington, this is VOA news. I'm Jee Abbey Lee reporting.

The United States has rejected Russian claims the chemical gas sarin that killed dozens of people in Syria last week came from an airstrike on a rebel-held munitions storage.

The National Security Council issued a report Tuesday and said the Syria regime and Russia are trying to "confuse the world community about who is responsible for using chemical weapons against the Syrian people" in this and earlier attacks.

The NSC reports said Syria's use of chemical weapons is "unacceptable" and poses a clear threat to the U.S. and the world.

It also called on the international community to make a statement that "this behavior will not be tolerated," although it did not specify possible consequences.

During a daily briefing Tuesday, White House press secretary Sean Spicer argued Syrian President Bashar al-Assad was worse than the leader of Nazi Germany, Adolf Hitler, because even Hitler didn't think to use chemical weapons.

Nazis gassed millions of Jews in concentration camps.

Spicer's comment drew immediate rebukes from the U.S. Holocaust Museum, the Anne Frank Center and a number of Democrats.

House minority leader Nancy Pelosi is calling on President Donald Trump to fire Spicer for downplaying the horror of the holocaust.

U.S. President Donald Trump says "North Korea is looking for trouble" with its nuclear weapons program and asked Beijing's cooperation in reining in Pyongyang.

Mr. Trump tweeted Tuesday "If China decides to help, that would be great. If not, we will solve the problem without them!"

This is VOA news.

White House spokesman Sean Spicer says President Donald Trump has seen the "troubling" video of a passenger being dragged off a United Airlines plane Sunday.

The video has unleashed a global social media firestorm and threats of a boycott.

Spicer told reporters at a White House briefing Tuesday, the incident was "unfortunate" but does "not necessarily need a federal response."

Because the Chicago to Louisville flight was overbooked, the crew asked passengers to voluntarily take another flight in exchange for financial compensation. When no one volunteered, the airline randomly selected four people, one of whom refused to leave until he was forcibly removal by three Chicago aviation security officers.

The video showing the man being dragged from the plane and later returning with a bloodied face was widely circulated on social media, drawing angry reactions.

Zambia's top opposition leader was arrested late Monday and has been held without charge, an opposition party spokesman told VOA.

He says the government is accusing presidential challenger and critic Hakainde Hichilema of treason and that the arrest reflects poorly for the African nation. VOA's Anita Powell reports from Johannesburg.

Zambia's outspoken opposition leader has been arrested for the second time in just over six months, part of deepening fallout from a contentious August poll that both contenders claim to have won.

Late Monday night, says opposition spokesman Charles Kakoma, police broke through the doors of opposition leader Hakainde Hichilema's upscale home, blocked the gates and doors to prevent escape, tear-gassed the occupants and then took Hichilema away.

Kakoma said police still had not charged Hichilema the morning after and had taken him to a police training academy for questioning. He said the party had been warned that this might happen because of an incident days before in which Hichilema's convoy crossed paths with President Edgar Lungu's motorcade as the two men were attempting to attend the same ceremony in western Zambia.

Anita Powell, VOA news, Johannesburg.

U.S. Navy says the USS Carl Vinson Strike Group is still participating in planned exercises with Australian Navy.

The announcement is in direct contrast to comments by the secretary of defense. Speaking at the Pentagon Tuesday, Secretary of Defense Jim Mattis told reporters the strike group originally was set to travel south for joint exercises with Australia but "canceled" its role there when the warships were directed north to the Western Pacific instead. Mattis said the move north was announced in an attempt to "explain why" the USS Vinson "wasn't in that exercise."

I'm Jee Abbey Lee in Washington.

That's the latest world news from VOA.