South Korean and U.S. troops staged a combined drill to strengthen their joint readiness posture against chemical, biological and radiological attacks by North Korea. 

The defense ministry said Thursday that the two nations’ commands in charge of chemical, biological and radiological threats conducted the Liberty Focus training from Monday to Thursday as part of the Freedom Shield exercise. 

The Liberty Focus drills are held every year to enhance the allies’ readiness in the event of a North Korean chemical, biological or radiological attack. 

The allies conducted command post exercises, tactical discussions and field training exercises based on various scenarios. 

The ministry said the Liberty Focus drill improved interoperability between the allies’ commands and significantly strengthened their ability and readiness to conduct combined operations.