South Korea's rail services will be disrupted on Friday as unionized workers continued a general strike for a third day. 

The Korea Railroad Corporation(KORAIL) said it plans to keep the operation rate of KTX bullet trains at 69 percent of usual levels, operating 219 trains on Friday. 

However, disruptions in train operations will likely be unavoidable as up to 100 KTX trains will not be running. 

The operation rate of slower Saemaeul and Mugunghwa trains will be 57 percent and 62 percent, respectively, while intercity subway trains in the capital region will operate at 82 percent. 

Cargo services will be most affected, with only 31 percent of freight trains in service compared to usual levels. 

As interviews and tests are scheduled for Friday and over the weekend at major colleges in Seoul as part of the annual college entrance exam, test takers are advised to check any changes in train operations.