Violent clashes in the National Assembly are not unheard of, reflecting the nation’s feisty brand of democracy. The trade agreement with the United States has been a particularly thorny issue, after huge demonstrations in Seoul, the capital, this year against the import of American beef.

Image Members of the opposition party were sprayed with fire extinguishers from inside as they tried to enter a parliamentary committee room. Credit... Kim Ju-seong/Yonhap, via Reuters

Thursday’s assault came after the opposition party had threatened to block the deal by force if necessary. Fearing an attack, members of the foreign affairs committee, under the control of the governing Grand National Party, had barricaded themselves inside the room as they met.

Security guards and aides from the governing party stood outside the barricaded doors, where scuffles broke out when a dozen opposition lawmakers showed up. The opposition lawmakers then used at least one sledgehammer and crowbars to tear through the doors, only to be thwarted by piles of furniture thrown up as a second line of defense.

The mayhem failed to prevent the pact from being formally introduced to the committee, a step in the process of bringing it to a full parliamentary vote.

The deal to lower tariffs and other trade barriers was signed last year by negotiators from South Korea and the United States but cannot take effect until ratified by lawmakers in both nations.