The disgraced Pakistani nuclear scientist Abdul Qadeer Khan was freed yesterday after spending five years under house arrest for selling atomic secrets to Iran, North Korea and Libya in the world’s biggest nuclear proliferation scandal.

A court declared Dr Khan, 72, a free man in a move likely to anger the United States and its allies. They have long sought to question him and believe that his international nuclear black market is still active.

Sardar Mohammad Aslam, Chief Justice of the Islamabad High Court, ruled that Dr Khan’s detention was unlawful after a closed-door hearing on a petition filed by the scientist, which was not challenged by the Government. “It’s a matter of joy. The judgment, by the grace of Allah, is good,” Dr Khan said outside his villa in Islamabad soon after news of the ruling broke. “I am finally vindicated.”

The man hailed as the father of Pakistan’s nuclear bomb said that he owed his freedom to the support of President Zardari and Yousuf Raza Gilani, the Prime Minister. He declined to comment on the charges that as head of Pakistan’s main nuclear facility he had masteminded a vast clandestine nuclear black-market network with tentacles spread over three continents. “I don’t want to discuss the past,” he said.

When Pakistan’s successful nuclear test in May 1998 created the world’s seventh nuclear power, he was hailed as a national hero. But he was dismissed in 2002 – reportedly under pressure from the US – as Western intelligence agencies began to expose his network. Their suspicions were aroused in 1995 after UN weapons inspectors discovered documents describing an offer made to Baghdad before the 1990-91 Gulf war. According to their reports Dr Khan had offered Saddam Hussein help to establish a uranium enrichment plant and had visited Iraq many times.

In 2004 Dr Khan admitted to having traded in bomb designs and nuclear technology, although he later backtracked on his confession. General Musharraf, the President at the time, pardoned him but placed him under detention in his house where he has lived in virtual isolation since. During the past year his detention had been relaxed gradually and he had been allowed to meet friends.

He gave a series of interviews after a new Government came to power last March but was barred from speaking to reporters by a July court ruling.

It was unclear whether his movements or activities would remain restricted. Barriers had been removed from the front of his house but security officials were still barring entry. “As far as I have been told, I will go anywhere in Pakistan without any restrictions and I will get whatever security that I had with me previously,” he said. “If I want to travel abroad I will have to seek permission from the Government.”

Pakistani officials say that they consider the case closed and have passed all relevant information about Dr Khan’s nuclear proliferation to concerned countries. US and international nuclear experts still want to question him.

Khan’s progress

- Born in Bhopal, India, in 1936. Went to Pakistan after Partition in 1947

- Studied science at Karachi University and joined Pakistan’s nuclear programme in 1972

- In 2004 admitted running proliferation ring. Pardoned by President Musharraf but held under house arrest

- In 2006 was revealed to be being treated for prostate cancer Source: Times database

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