An opposition lawmaker accused of taking bribes appeared before a Seoul court Thursday to attend a hearing to review the legality of his arrest.

Rep. Kim Jae-yun of the main opposition New Politics Alliance for Democracy (NPAD) showed up at the Seoul Central District Court at around 2 p.m. after the prosecution, in an unprecedented move, vowed to forcibly detain him.

"I have sincerely prepared to attend a court hearing from the beginning," Kim told reporters before entering a court building.

Kim, however, denied bribery charges against him, saying, "I have never received money."

Earlier in the day, the prosecution sent a team of investigators to the National Assembly building to detain five sitting legislators -- Kim, Shin Hak-yong and Shin Geh-ryeun of the same party, and Cho Hyun-ryong and Park Sang-eun of the ruling Saenuri Party -- who have been refusing to show up to the court hearings.

The investigators, after hours-long confrontation, left the building after Shin Hak-yong and Shin Geh-ryeun had promised to appear for the court hearings.

Shin Hak-yong will appear at the Seoul court at 4 p.m. Thursday while the court is rescheduling a hearing for Shin Geh-ryeun, officials said.

The prosecution said it is still locating the whereabouts of Cho and Park, who are being investigated in separate bribery cases.

The prosecution move comes as legislators are immune from arrests while the National Assembly is in session. Lawmakers are scheduled to convene for a plenary session on Friday.

Cho is under suspicion of taking bribes worth 160 million won (US$156,000) from railway parts supplier Sampyo E&C in return for awarding the private company contracts since August 2008.

Kim, Shin Hak-yong and Shin Geh-ryeun have been under investigation since early August over corruption allegations as well.

Kim and Shin Geh-ryeun are each accused of taking about 50 million won in bribes from a local vocational training school earlier this year in return for helping pass a bill in favor of the school.

The passage of the bill to revise the vocational education law in April helped change the name and upgrade the status of what is now known as Seoul Art College.

Shin Hak-yong, the chairman of the National Assembly's education and culture committee, is accused of proposing a law governing privately run kindergartens after taking some 38 million won from an association of private kindergartens.

Saenuri Party legislator Park Sang-eun is under suspicion of taking more than 600 million. (Yonhap)