Liveblogging the event from his Twitter account, Athar was unaware of the situation before US president Barack Obama's announcement. The al-Qaida leader was killed in a "firefight" during a ground operation outside Islamabad, Pakistan.
Tweeting at around 9pm BST, Athar first wrote: "Helicopter hovering above Abbottabad at 1AM (is a rare event)."
Minutes later, he added: "All silent after the blast, but a friend heard it 6 km away too... the helicopter is gone too."
After realising that Bin Laden had been taken out, he said: "Uh oh, now I'm the guy who liveblogged the Osama raid without knowing it."
Athar's Twitter description reads: "An IT consultant taking a break from the rat-race by hiding in the mountains with his laptops."
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> Osama Bin Laden death leaks first on Twitter