Peru's defense minister announced on Wednesday an investigation into allegations of military corruption in the world's No 1 cocaine-producing valley, after The Associated Press reported that the armed forces turned a blind eye to the ferrying of cocaine abroad by small planes.

Jakke Valakivi, the minister said the government and the joint armed forces command would investigate together.

Peru's armed forces have failed to effectively impede an "air bridge" that has delivered more than a ton of cocaine a day to Bolivia in flights that stepped up in tempo in the past few years, according to prosecutors, drug police, former military officers and current and former US drug agents.