Four Georgian soldiers including a colonel have been killed in a landmine blast in Afghanistan. It is thought to be the biggest loss of life for the small ex-Soviet republic since it deployed to Afghanistan as part of the NATO led mission.NATO Secretary General, Anders Fogh Rasmussen, who is visiting the Georgian capital, Tbilisi, paid tribute to them. Although Georgia is not a member of NATO, it currently has 925 soldiers serving with the NATO -led International Security Assistance Force in Afghanistan.