SEOUL : University students across South Korea will stage protests on Wednesday as anger grew over ballot paper shortages at recent local elections.

Dozens of polling stations nationwide were short of around 7,000 ballot papers on June 3 election day, official data showed.

The supplies were eventually replenished on voting day, but the mishap fuelled fury in a nation where unfounded claims of vote tampering have found a growing audience.

The local election was the first nationwide vote since President Lee Jae Myung took office following conservative Yoon Suk Yeol's ouster over his brief martial law declaration in late 2024.

Lee's ruling liberal Democratic Party won most races in the vote for mayors, local government officials and assembly members, but failed to flip the critical Seoul mayoral seat.

The head of the election watchdog has resigned over the ballot paper row, but authorities have not offered to hold a new vote, sparking huge protests at the weekend.

Student unions at 18 universities said they will hold new demonstrations from 6 pm Wednesday.

"We are determined to protest because people are universally outraged regardless of political affiliation," Hwang In-seo of Yonsei University's student council, told AFP.

Analysts say the National Election Commission, a constitutional body with limited external oversight, has long faced gaps in internal discipline and review mechanisms.

A Seoul court this week ordered evidence from an affected polling station in the capital be preserved for investigation, while local media reported prosecutors and police had agreed to set up a joint investigation team.

The evidence includes ballot boxes and CCTV footage, a representative of the Seoul Eastern District Court told AFP.