An internal rift at the Unified Progressive Party is escalating, as hundreds of members clashed Saturday over how to revive the party torn apart by alleged election fraud.

The left-wing minor party has been mired in a factional division since earlier this month when it announced the fairness of its primary to select the party's proportional representation candidates for the April 11 elections had been seriously compromised.

The party has since recommended its leadership and all six lawmakers elected under the proportional representation system should resign over the scandal. A female lawmaker elected through the system has offered to resign, but there have been no such offers from the other five.

The mainstream faction loyal to the East Gyeonggi Coalition, an allegedly pro-North Korean bloc, rejected the party's internal investigation of the scandal and called for a ballot of all party members to decide the fate of the five other lawmakers-elect.

The rival minority faction called for the resignation of all six lawmakers elected through the proportional representation system, and for the appointment of an interim emergency committee to handle party affairs.

The differences came to a head Saturday night when some 100 members of the mainstream faction dashed to the stage as the party's central committee meeting was underway.

Cho Joon-ho and Rhyu Si-min, two of the UPP's co-leaders who headed the internal probe, were assaulted and Cho's clothing was torn.

Earlier on Saturday, Lee Jung-hee, a UPP leader who was the figurehead for the East Gyeonggi Coalition, stepped down ahead of the central committee meeting. That move was immediately followed by the resignations of three other co-chairs of the party, including Cho and Rhyu.

Lee has claimed the East Gyeonggi Coalition was dissolved a decade ago, but others say the dominant faction was active after 2005.

Seven UPP candidates were elected through direct elections and six others won parliamentary seats under the proportional representation system that allocates seats to parties according to the numbers of votes they receive.

The UPP, which was created just five months ago, has become the third-largest party in the 300-seat National Assembly, which is set to begin its four-year-term later this month.

(Yonhap News)