Turkey's Interior Minister Suleiman Soylu says army, village guards will also help secure voting at 167,000 ballot boxes.
Suleiman Soylu, speaking at a news briefing in Ankara, said a total of 251,788 members of the security members plus 128,445 gendarmes had been assigned referendum duty, Anadolu Agency reported.
Six thousand Turkish army personnel will also be on duty as a backup force, Soylu said.
Soylu added that over 51,000 village guards in 26 different cities and 18,700 volunteer guards would serve as well.
More than 55 million Turkish citizens will vote on wide-ranging constitutional changes on April 16. Voters will go to over 167,000 ballot boxes nationwide.