The leader of South Korea's second-largest umbrella labor union has been indicted on charges of leading last year's violent rallies in downtown Seoul, prosecutors said Tuesday.

Han Sang-gyun, the head of the Korean Confederation of Trade Unions, is accused of orchestrating a massive anti-government protest on Nov. 14 that led to violent clashes with the police and some ten other rallies last year, the Seoul Central District Prosecutor's Office said.

The labor union leader faces five charges, including disruption of the execution of public duty and damage of public property.

Prosecutors said Han is suspected of inflicting injuries to 90 police officers and damaging 52 police buses as well as illegally occupying the streets by leading protesters on Nov. 14.

Han has been taken into custody since he turned himself in to police in December after weeks of hiding out at Jogye Temple, the main Buddhist temple in central Seoul.

Prosecutors said they need further investigation to apply a charge of sedition against Han, which if applied would be the first time in nearly 30 years.

Police had originally included the charge when they referred the case to the prosecution after a preliminary investigation.

"While (we) respect the decision made by the prosecutors, there is no change in the police's stance that the sedition charge should be applied," Kang Sin-myeong, the National Police Agency Commissioner-General said in a press conference.

"Considering that the violent November rally had been planned for a long time and the level of violence expressed goes over the boundary of a protest, it is right to apply the sedition charge against Han," the national police chief said.

The crime of sedition refers to "the act of destruction through assault or intimidation by gathering multiple forces."

The last time investigative authorities charged a suspect with sedition was in 1986 when protesters violently clashed with police in the western port city of Incheon.

Prosecutors said they have indicted seven others who allegedly incited violence at the November rally and were investigating three more in custody for the probe.

Hundreds of others are under investigation by police over similar charges, police said. (Yonhap)