(RNS) The South Korean government warned Christian missionaries in the country Nov. 3 not to travel to Iraq after five South Koreans were taken into protective custody and flown home.

South Korea has more than 12,000 missionaries in 145 countries - second only to the United States, according to the Korean World Missions Association, and many are known for their efforts to spread Christianity to communist and Muslim nations, Reuters said. South Korea also has the third largest foreign military contingent in Iraq, behind the United States and Britain.

A South Korean interpreter, who was also a devout Christian, was beheaded by militants in June.

According to the Korean Yonhap news agency, the missionaries flown back to Seoul had name tags with the word "martyr" after their name.