A woman casts her ballot at a polling station during a referendum in Ankara, Turkey, April 16, 2017. REUTERS/Umit Bektas

ANKARA (Reuters) - Votes in favor of Turkish constitutional changes that could give President Tayyip Erdogan sweeping new powers stood at 63 percent with just under a quarter of ballots counted, broadcaster NTV said on Sunday.

Polls closed at 4 p.m. (9.00 a.m. ET) in the east of the country and at 5 p.m. elsewhere.