LIVE: Turkey votes on presidential system in key referendum

3:40 p.m. - Supreme Election Board (YSK) head Sadi Güven said in a statement that seals featuring the word "yes" instead of "choice" would be counted as valid. 

He also stated that ballot papers on which YSK seals were applied to the front instead of the back would also be deemed valid. 

Earlier, "yes" seals had been distributed to voters in the Reyhanlı district of the southern province of Hatay before being collected and replaced with the original "choice" ones.

3:23 p.m. - EU Minister Ömer Çelik cast his vote in the southern province of Adana. 

"Now the nation has the word and the decision. I expect a powerful result for the future of our country. God willing everything will be fine," Çelik said.

2:45 p.m. - Chief of General Staff Gen. Hulusi Akar cast his vote in a school in the Çankaya district of Ankara where authorities earlier searched for biological and chemical weapons.

12:30 p.m. - Nationalist Movement Party (MHP) leader Devlet Bahçeli cast his vote in Ankara, calling it a significant turning point in the life of the nation.

"I'm happy that I carried out my civic duty. Turkish politics will head toward a new structuring regarding the future," he told journalists.

11:45 a.m. -  President Recep Tayyip Erdoğan cast his vote in Istanbul, calling the referendum not an ordinary vote. 

"This referendum is not an ordinary voting. We had plenty of elections aimed at the parliamentary system in the history of the Republic. We had some referendums, but this one is to decide whether to change the governance system. I believe that our people will decide for a faster...