ISLAMABAD- Security was beefed up today around the Prime Minister House after PAT workers began to gather outside official residence of the premier. Heavy deployment of security personnel was made outside the PM House while aerial surveillance of the red zone is also being done. Hundreds of PAT workers were standing eyeball to eyeball with security personnel in fast changing events. Earlier, Dr Tahriul Qadri, chief of Pakistan Awami Tehreek (PAT), directed his followers to lay a siege of the Parliament House. "Don't let anybody go inside or come outside of the Parliament," he told his charged supporters. Qadri asked his workers not to confront personnel of the Pakistan Army in anyway whatsoever, saying anybody who does that will be expelled from the PAT. "Everybody should chant Pak Fauj Zindabad," he ordered.