Turks head to polls in historic referendum

Turkey's tense referendum on constitutional amendments could greatly expand the powers of Turkish President Recep Tayyip Erdogan.

Polling stations opened at 7 a.m. (0400 UTC) in the east of Turkey on Sunday and an hour later in the west. Voting closed at 5 p.m. (1400 UTC) with results expected during the evening hours.

President Recep Tayyip Erdogan cast his ballot in Istanbul and told reporters after voting: "We have held referendums before. But this referendum is now about a new administrative system for the Republic of Turkey, it's a choice for change and transformation."

Prime Minister Binali Yildirim has cast his vote in the western province of Izmir and said: "Whatever the result is, we will hold it in high esteem. The decision of our nation is the most beautiful decision."

However, one voter who said he was going to mark his ballot 'no' said  "I don't want to get on a bus with no brake system. A one-man system is like that."

Over 55.3 million people are eligible to cast their ballots in 167,140 polling stations across the country on Sunday. Voters living abroad have already cast their ballots at Turkish diplomatic missions.

The most recent opinion polls predict that the result will be close, but give a narrow lead for the "Yes" vote. Around 10 percent of voters were undecided a day before the vote.

Security will be tight during Sunday's vote, with nearly 34,000 police on patrol in Istanbul alone. The militant "Islamic State" (IS) group has called for attacks against the referendum.

There were reports of a shooting at one voting station which led to "two dead, four wounded after dispute at referendum voting site in Diyarbakir. Soldiers and authorities at the scene"

The incident was apparently caused by two brothers with opposite views shooting at each other. During the incident one of the brothers died, as did their father, who attempted to break up the fight.

Election observers were "reportedly beaten and removed" from a voting station in Urfa Ceylanpinar

Read: What you need to know about the Turkish referendum

Constitutional overhaul

Erdogan has called on Turkish citizens to cast their ballots in favor of 18 constitutional changes that would abolish the office of prime minister and give executive power to the president.

The package of amendments would also give the president the authority to draft the budget, declare a state of emergency and issue decrees to ministries without parliamentary approval.

Erdogan and his ruling Justice and Development Party (AKP) say the constitutional reforms are necessary to streamline the Turkish government and to counter security threats, including a failed military coup and a series of deadly bombings claimed by IS.

Critics argue that the amendments will cement Erdogan's hold on power with fewer checks and balances.

Erdogan, who came to power as prime minister in 2003, before assuming the presidency in 2014, could end up serving as president through 2029 if the "Yes" vote prevails on Sunday.

Read: Observers to guard against voter fraud in Turkey's referendum

Contentious campaign

The referendum campaign has divided the nation and caused relations between Ankara and Europe to hit a new low.

Germany and the Netherlands barred Turkish ministers from holding rallies in support of the "Yes" vote, prompting Erdogan to call the moves "Nazi acts." He also said Turkey could reconsider ties with European Union after years of seeking membership in the EU.

The referendum vote also takes place during a strict state of emergency put in place after last July's failed coup.

The opposition "No" campaign has been hampered by restrictions, according to observers including the Organization for Security and Cooperation in Europe (OSCE).

rs/jm (AP, AFP, dpa, Reuters)