Ayman al-Zawahiri: How US strike could kill al-Qaeda leader - but not his family

Just over an hour after sunrise on 31 July, long-time al-Qaeda boss Ayman al-Zawahiri walked out onto the balcony of a downtown Kabul compound - reportedly a favourite post-prayer activity of the veteran Egyptian jihadist.

It would be the last thing he would do.

At 06:18 local time (01:38 GMT), two missiles slammed into the balcony, killing the 71-year-old but leaving his wife and daughter unscathed inside. All the damage from the strike appears to be centred on the balcony.

How was it possible to strike so precisely? In the past the US has faced criticism for strikes and targeting errors that have killed civilians.

But in this case, here's how the type of missile, and a close study of Zawahiri's habits, made it happen - and why more strikes could follow.