New Delhi, Aug 6: The Indian security agencies are watching closely a major event that is to take place in London on August 12. This coupled with the fact that the event called Referendum 2020 will be held three days prior to Independence Day, for which a very high alert has already been declared. An Intelligence Bureau official tells OneIndia that the event at London has the backing of the ISI. It is a way of announcing on the world stage the return of the Khalistan movement. It is unfortunate that the UK government decided not to ban the event, the officer also said.