ANKARA (Reuters) - Turkey's main opposition will demand a recount of up to 60 percent of votes cast in a referendum that could give President Tayyip Erdogan sweeping powers, party deputy chairman Erdal Aksunger said on Sunday.
The Republican People's Party (CHP) earlier said that "illegal acts" were being carried out in favour of the government in the referendum.
Turkey's High Electoral Board said it would count ballots that had not been stamped by its officials as valid unless they could be proved fraudulent, citing a high number of complaints that its officials at polling stations had failed to stamp them.
Votes in favour of the constitutional changes narrowed to 51.7 percent with around 95 percent of ballot boxes opened, the state-run Anadolu news agency said. "No" votes have taken the lead in Turkey's three largest cities, Istanbul, Ankara and Izmir, and the mainly Kurdish southeast, the data showed.
(Reporting by Gulsen Solaker; Writing by Tuvan Gumrukcu; Editing by David Dolan)