SEOUL, Nov. 23 (Yonhap) -- South Korea's parliamentary secretariat said Wednesday it may take legal action against an opposition lawmaker who set off a tear gas canister in the chamber to block the ratification of a free trade deal with the United States.

South Korea's ruling party lawmakers on Tuesday rammed a long-pending free trade agreement with the U.S. through parliament amid chaos and scuffles as Kim Sun-dong, an opposition lawmaker, set off a tear gas canister in a bid to block its passage.

"The National Assembly Secretariat is reviewing related regulations to take potential legal action against him," said Han Jong-tae, a parliamentary spokesman.

Under local criminal law, a person can be sentenced to three years in prison or be fined up to 7 million won ($6,081) if he disrupts the National Assembly chamber or nearby areas in an attempt to block parliamentary deliberation.