What Has Happened To A.Q. Khan?

I'm currently reading Atomic Bazaar by William Langewiesche, which contains his two-part article about A.Q. Khan originally published in The Atlantic. The article concludes with the fact that A.Q. Khan, after he delivered the bomb, has ceased to be relevant to the Pakistani establishment, who placed him under house arrest after being caught red-handed selling nuclear technology to anybody who wanted it.

No one has heard from him since. A.Q. Khan is a proud man, and is probably wondering why he's being treated like a criminal when the common man considers him a folk hero for endowing Pakistan with the august status of a nuclear power. Who knows what threats the government has made against him, but I'm very sure A.Q. Khan resents it and is willing to spill the beans, so to speak, that the government knew of his activities and even actively encouraged them.