Ankara. A pair of news outlets in Turkey provided different partial results from the country's presidential election Sunday, with the state-run news agency indicating with three-quarters of ballot boxes counted that President Recep Tayyip Erdogan would squeak out a victory but an opposition-leaning agency saying the contest was headed toward a run-off.

The state-run Anadolu Agency said Erdogan was leading with 51% of the vote, while Kemal Kilicdaroglu, his main challenger, had garnered 43% after 75% of ballot boxes were tallied. The ANKA news agency said that with ballots from 76% of boxes counted, Erdogan had won 48% compared to Kilicdaroglu’s 46%.

If neither candidate secures more than 50%, the two will compete in a run-off vote on May 28. Turkey's election authority, the Supreme Electoral Board, said it was providing numbers to competing political parties “instantly” but would not make the results public until the count was completed and finalized.

Further complicating the picture, the opposition candidate's party accused Anadolu of manipulating results, insisting that Kilicdaroglu was narrowly leading with 47.42% to Erdogan's 46.80%.

Istanbul Mayor Ekrem Imamoglu, who campaigned on behalf of Kilicdaroglu, alleged ruling party monitors were “regularly objecting” to results from ballot boxes that placed Kilicdaroglu ahead.

Erdogan has governed Turkey as either prime minister or president for two decades. In the run-up to the election, opinion surveys had indicated the increasingly authoritarian leader narrowly trailed his challenger.

The race, which largely centered on domestic issues such as the economy, civil rights and a February earthquake that killed more than 50,000 people, had appeared to be shaping up as the toughest re-election bid of the Turkish leader’s 20-year rule.

With the partial results showing otherwise, members of Kilicdaroglu’s center-left, pro-secular Republican People’s Party, or CHP, disputed Anadolu’s numbers, contending the state-run agency was biased in Erodgan’s favor.

“We are ahead,” tweeted Kilicdaroglu, 74, who ran as the candidate of a six-party opposition alliance.

Omer Celik, a spokesperson for Erdogan's Justice and Development, or AK, party, in turn accused the opposition of “an attempt to assassinate the national will” by claiming the state news agency was distorting the results. He called the opposition claims “irresponsible.”

The election could grant Erdogan, 69, another five-year term or see him unseated by Kilicdaroglu, who campaigned on a promise to return Turkey to a more democratic path and to repair an economy battered by high inflation and currency devaluation.