As a result of the explosion earlier this morning a heavy cloud hanging over the refinery is now moving slowly in an easterly direction. There is nothing to suggest the cloud is toxic but as a precaution we are asking residents in Hemel Hempstead, and the surrounding areas towards St Albans to keep their windows and doors close and stay in. All updates in relation to the nature of the cloud and the incident will be placed on the tape immediately. We are asking people not to contact the emergency services unless they have a genuine call for assistance. Everything possible is being done at this stage.