Nuclear scientist Dr Abdul Qadeer Khan has said that Pakistan has the capability to shoot down unmanned surveillance drone aircrafts, adding that the country was facing internal threats rather than external. Talking to a private TV channel on Monday he said that they had built missile in Kahuta some 15 years ago which have the capability to shoot down drones. Dr Khan said the army has taken oath for the security of borders but what is the use of oath if violation of border continues. “Ziaul Haq was a dictator but he was a patriotic ruler… the current rulers are corrupt and robbers,” he said. Dr Khan said, “Pakistan’s defence looks very impenetrable externally, but it is vulnerable internally due to the internal situation of the country. We were hoping that the nation would focus on progress, education and industrial advancement but rulers have plundered the public property for many years.” “Even having nuclear capability, it is a wrong perception that we can not take action against the United States, England or France because we have accumulated nuclear system against India,” he said.