Hamza's Son Worked in Westminster

The Sun is reporting that the son of Abu Hamza, who was sentenced to three years in Yemen for planning terrorist attacks there, had worked right next to the Houses of Parliament. He had got a labouring job with Westminster City Council and one of those jobs included relaying the turf of Abingdon Green. This is an area very close to Parliament where MPs are often interviewed.

One security source said:

This is a man with a history of being a highly motivated terrorist. But he was free to wander around the lawns near parliament. The obvious fear was that he could have buried or concealed a device. He could also have brought a bomb close to politicians.

A couple of weeks ago it came to light that he had been working on the London Underground. In both cases he didn't tell his employers of his terrorist past and this wasn't flagged by searches because it took place abroad.

Now, why is it that this convicted terrorist has had two jobs in two extremely sensitive areas of London? Is it just an unfortunate coincidence?