Election irregularities probes launched in Istanbul following Turkish opposition victory against ruling AKP

Turkish courts have launched tens of investigations into alleged voting irregularities in Istanbul's local elections, state media reported on Thursday.

The main opposition Republican People's Party (CHP) won the mayoralty in Ankara and Istanbul in addition to the party's stronghold Izmir, wresting the country's largest cities from the hands of the ruling Justice and Development Party (AKP).

The Istanbul mayoral election has been particularly contentious, with official complaints by the AKP delaying the inauguration of CHP politician Ekrem Imamoglu as mayor for weeks.

President Recep Tayyip Erdogan called last month for the cancellation and re-run of the vote, a decision which is still pending before Turkey's Supreme Electoral Board (YSK).

While the decision is pending, the YSK has ordered district electoral officials to oversee inspections of ballot box officials in Istanbul.

These inspections focus on the Maltepe, Kadikoy and Atasehir districts of the city, all of which were won by the CHP.

Prosecutors have launched 32 investigations into voting irregularities, which Erdogan last month alleged were tied to "criminal" activity, and summoned more than 100 polling station officials for questioning.

The suspects are being questioned over alleged violations of election law and abuse of their positions in the counting of votes and entering of dates.

While some of the criminal complaints were launched by the AKP and its ally the Nationalist Movement Party (MHP), others were filed by district election boards, state news agency Anadolu reported.

AKP deputy chairman Ali Ihsan Yavuz has alleged that "biased" people were appointed ballot box officials before the election as part of an orchestrated effort to swing the vote.

"We very clearly see that there have been some fully organised work and operations to cheat at the ballot boxes, starting from two years ago," he said according to Reuters, adding that more criminal complaints were due to be filed.

Similar complaints have been made in previous years by opposition figures, for whom the CHP victory over Istanbul and Ankara is a first major victory.

Both Istanbul and Ankara were governed by the AKP and its predecessors since 1994.

The CHP for its part has said that investigations have not indicated any irregularities or criminal acts.

"As a result of the inspections completed by the District Election Boards after the YSK's interim rulings, there are no findings that require an annulment of the elections," the CHP's legal commission said on Twitter.

"Prosecutors seeking testimonies as part of the appeals is routine and does not mean there were irregularities in the elections."

A potential re-run of the Istanbul local elections is tentatively scheduled for 2 June, but the YSK may choose a later date if it decides to annul the elections.

Erdogan also ordered a cut to funds transferred from Turkey's treasury to local municipalities in a presidential decree published in the Official Gazette.

Opposition voices had speculated that the government may cut funds to local municipalities following the CHP victories in Istanbul and Ankara.

The treasury will take a 5 percent monthly cut of revenues obtained from metro systems built by the Transport Ministry but operated by the municipality, according to the ruling.