"Our concerns over the potential for proliferation activities by Khan are well known to the Pakistani government," State Department spokesperson Ian Kelly told reporters in Washington on Wednesday.
"We believe that he remains a proliferation risk. We are following this closely, and of course, the Pakistani government, as I say, is well aware of our concerns about Khan," he said.
Kelly was responding to questions about the Lahore high court on August 28 suspending the "security protocol" accorded by the government to Khan and directing authorities not to restrict his movements. Khan has been accused of running a clandestine proliferation network.
Acting on a petition filed by Khan who sought removal of the restrictions on his movements, the court said the scientist was a free man and could go wherever he wanted.
Responding to another question, Kelly said Khan's activities are well known.
Image: Pakistan nuclear scientist A Q Khan| Photograph: Mian Kursheed
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