ISTANBUL, Dec. 31 (Xinhua) -- Security measures were tightened on Monday for New Year celebrations in Istanbul, Turkey's most populous city.

A total of 39,000 police officers, 4,000 gendarmerie members as well as coast guard teams "will be on duty to guard the city and provide the security at the maximum level," Istanbul Governor Ali Yerlikaya said in a written statement.

Twenty-four-hour patrol shall be enforced in the metropolis on Monday and Tuesday, with 17,000 police officers to be on duty in the central Beyoglu district alone, according to the Istanbul police.

Some mounted officers are assigned to the most populated areas of the city, with all the roads leading to the iconic Istiklal Avenue in the Beyoglu district to be closed to traffic as of 15:00 local time (1200 GMT).

In 2017, a Uzbek national killed 39 people who were celebrating the New Year at Istanbul's Reina nightclub, a shooting spree claimed by the Islamic State militant group.