Security is high alert outside a polling station during by- elections in NA-120 constituency in Lahore on Sunday, September 17, 2017. Polling for the NA-120 by-election started at 8am across 220 polling stations in the provincial capital. A total of 44 candidates are contesting for the National Assembly seat from Lahore. Pakistan Army personnel are supervising the polling process. The first vote of the election was cast at 8am on Sunday.