I was in my office at UCL, just two blocks away from the bus bomb. I heard the explosion, but assumed it must be something to do with all the building work around our site, until I heard all the sirens and the air ambulances.

It is a terrible thing to have happened, but I suppose after 9/11 and Madrid, we were expecting something like this. I sometimes think about terrorist attacks when I am on a crowded tube train, but you can't let it get to you or the terrorists have won. I find it hard to understand the mentality of people who arrange to murder and main innocent people they have never even met for the sake of their cause, whatever it may be.

Sally