Doctors are set to hold a large-scale rally on Sunday in Seoul to protest against the government's plan to expand medical school admissions quota amid the government's stern measures against doctors' collective action.

The Korean Medical Association(KMA), the country's largest doctor's group, plans to hold a massive rally at 2 p.m. in Yeouido, Seoul.

A KMA official said that about 20-thousand doctors notified their intent to take part in the rally, adding that the number of participants is expected to be much larger than in doctors' rallies held in recent years.

As soon as the government's Thursday deadline for trainee doctors' return-to-work order passed, the police conducted raids on the homes and offices of former and incumbent KMA officials on Friday on suspicion of encouraging the trainee doctors to walk off the job en masse and abetting the strike.

The raids were conducted after the Health Ministry filed a complaint against five people, including the chief of KMA's emergency steering committee.

The police secured related materials through the raids and notified the KMA leadership to appear for questioning on Wednesday.

Starting Monday, the Health Ministry plans to check on trainee doctors who failed to return to work and file a complaint with the police.