ANKARA Turks approved by a narrow margin an April 16 referendum to change the constitution and hand President Tayyip Erdogan sweeping powers.
The opposition and overseas observers say the vote was riddled with irregularities, including the electoral board's decision to accept ballots that had not been officially stamped by authorities at polling stations.
The following is a timeline of events on the day of the vote.
6:01 a.m. - Polling station officials receive SMS from High Electoral Board (YSK) reminding them to stamp envelopes and ballot sheets.
7:00 a.m. - Polls open in Turkey's eastern and mainly Kurdish southeastern provinces. Soon after, the Turkish bar association begins to receive complaints about voters being given ballots without the official electoral stamp.
8:00 a.m. - Polls open nationwide.
3:30 p.m. - CNN Turk reports YSK would accept ballots with the "Yes" stamp normally used by voters to mark their choice in parliamentary elections, rather than the more neutral "Preference" stamp created for the referendum. YSK later confirms this in an SMS to polling officials, and online.
4:00 p.m. - Polls close in eastern Turkey, where counting begins.
5:00 p.m. - Polls close nationwide. Counting starts across the country.
5:10 p.m. - With 11.28 pct of ballot boxes open, state-run Anadolu Agency says "Yes" vote is at 66.26 pct.
5:10 p.m. - CNN Turk reports YSK will accept ballots without the official electoral stamp. YSK later confirms this via SMS and online.
6:55 p.m. - Vote in Istanbul, Turkey's biggest city, turns in favour of "No". The "No" vote ultimately takes the city by 51.35 pct.
7:00 p.m. - 86.97 pct of ballots open, "Yes" at 52.87 pct.
7:24 p.m. - Ankara goes for "No". Turkey's three biggest cities - Istanbul, Ankara and Izmir, have all voted "No".
7:41 p.m. - 95.9 pct of ballots open, "Yes" at 51.56 pct.
7:45 p.m. - State broadcaster TRT declares the race for "Yes".
8:20 p.m. - 97.8 pct of ballots open, “Yes” at 51.34 pct.
8:27 p.m. - Erdogan tells PM Yildirim result of referendum clear, presidential sources say.
10:14 p.m. - Erdogan says unofficial results show around 25 million "Yes" votes, 1.3 million more than "No".
(Sources: Reuters, Anadolu Agency, CNN Turk, TRT, YSK High Electoral Board)
(Compiled by Reuters bureaux in Ankara and Istanbul)