Welcome to the NewsHour. Today, for the first time since South Korea became a democracy

some 40 years ago, a South Korean president declared martial law. But hours later, the opposition

and members of his own party in parliament rejected the order, and President Yun Suk Yul has now

rescinded it. Nick Schiffrin is here following this story. Nick, what's the latest?

Jeff, a senior administration official tells me tonight,

the U.S. said to South Korean officials

that Yuen's declaration was, quote, untenable

and urged them to reverse it quickly.

And the official warns that Youn might not survive this episode

that could have threatened the stability

of one of the U.S.'s most important allies.

In Seoul tonight, they storm the institution they pledged to protect. Special Forces soldiers

acting under martial law fought with protesters and pushed back opposition politicians from entering parliament.

Inside, the only thing that stops soldiers from the parliament floor, furniture deployed by opposition staffers.

That allowed Parliament to vote down the martial law declaration 190 to zero.

A step demanded not only by the leader of the opposition, who live streamed himself jumping

over the fence to get to parliament, but also by the leader of Yun's own party, who said,

quote, the president's declaration of martial law is wrong.

With our people, we will stop it. Afterwards, security forces rushed out of parliament.

Protesters celebrated a battle won, and Yun revoked his own declaration.

I will accept the National Assembly's demand and lift martial law through a cabinet meeting.

Six hours earlier, Yun, whose approval rating has been under 20 percent and whose resisted investigations into his wife, accused the opposition of being infiltrated by North Korea.

...