By Euronews
This is the scene inside the House of Commons as MPs learned about the attack which had just taken place on the street.
The deputy speaker told the assembled politicians that the session was ending and there would be no statement until the information was clarified. However, he told them not to leave the building.
A number of MPs were caught up in the incident with one going to the aid of a policeman who had been stabbed at the entrance to the building.
