BOGOTA, Jan 16 - Colombia on Friday launched a $1.68 billion project to develop a so-called anti-drone shield to protect the country from attacks by unmanned drones operated by illegal armed groups, the defense minister said.

Colombia has been involved in an ongoing internal armed conflict for six decades that has left more than 450,000 dead. Conflict in the Andean nation has involved the military and police forces, leftist guerrillas, criminal gangs formed by former right-wing paramilitaries and drug cartels.