A group of doctors are seen at a hospital in Seoul, Tuesday. (Yonhap)

The Health Ministry on Tuesday said it was considering filing criminal complaints with the police against the trainee doctors who are leading the protest against the government's plan to expand the annual medical school student quota.

“We are considering filing police complaints on the trainee doctors who led the walkouts,” said Second Vice Health Minister Park Min-soo. “Details as to when the police complaints will be filed and who it will be filed against will be decided later after further discussion.”

With close to 9,000 trainee doctors having walked out from their jobs, the ministry also said it would begin suspending the licenses of doctors who failed to heed the government’s return to work orders from Tuesday.

After inspecting up to 50 training hospitals on Monday, the ministry said it secured evidence that around 7,000 trainee doctors have remained off work.

"On Monday, the Ministry inspected up to 50 training hospitals and gathered evidence of noncompliance involving more than 7,000 doctors," said Kim Kook-il, head of the Health Ministry’s emergency response team. “We will be taking administrative action against them first as per the Medical Service Act.”

After conducting further inspections at up to 100 training hospitals, Park told reporters that the ministry found a total of 8,983 trainee doctors had left their workplaces as of 8 p.m. on Monday. The Health Ministry stated that it will “begin to take administrative action” against doctors who failed to heed the government’s ultimatum by sending out advance notices of license suspensions starting Tuesday.

Although doctors submitted resignation letters before walking out of their jobs, the government maintained its stance that these were not valid as the government had already issued an executive order for them to remain at their jobs under the Medical Service Act. The government argues that, under the act, doctors are obligated to continue practicing medicine.

Doctors are subject to a license suspension for up to one year and could face three years in prison or a fine of up to 30 million won ($22,455) for not complying with government orders.

Second Vice Health Minister Park Min-soo speaks to reporters during a press conference on Tuesday. (Yonhap)