Security heads of 31 participating nations, including Pakistan, will tomorrow take stock of the security in Commonwealth Games village and venues where a four-layer protection will be provided during the fortnight-long mega sporting event in New Delhi in October.Live security demonstration will be given to the representatives of the Commonwealth countries tomorrow at the Games village at Yamuna Bank and Jawaharlal Nehru stadium where the opening and closing ceremonies will be held. Over 10,000 athletes from 71 countries and 500,000 spectators are expected to take part in the Games to be held from October 3-14.