Iran's judiciary confirmed on Wednesday a death sentence for a German-Iranian national over a deadly mosque bombing in 2008, a decision Berlin described as "unacceptable".

"Jamshid Sharmahd's sentence has been upheld by the Supreme Court," judiciary spokesman Massoud Setayeshi told reporters in Tehran, saying "measures" ahead of the 68-year-old's execution "will be taken later".

German Foreign Minister Annalena Baerbock said the decision was "unacceptable" and Sharmahd had "never had anything like a fair trial".

A Sudanese war crimes suspect, part of the Islamist regime ousted in 2019, has escaped jail as heavy battles rocked the country Wednesday, heightening fears for a fragile ceasefire.

On the second full day of a three-day truce, witnesses reported "heavy air strikes" in East Nile, east of the capital, and "a huge explosion in the direction of a paramilitary camp".

Warplanes flew over northern suburbs of Khartoum, drawing heavy anti-aircraft fire from the paramilitaries, witnesses told AFP.

A powerful Iranian cleric, a member of the Assembly of Experts that selects the country's supreme leader, has been killed in an armed attack, officials said Wednesday.

The attack is believed to be the most significant in years against a cleric in Iran.

"Ayatollah Abbas Ali Soleimani was killed this morning in an armed attack... the assailant was also arrested and is now being investigated," IRNA news agency reported, citing a security official for the northern province of Mazandaran where the killing occurred.

A wanted Sudanese war crimes suspect has confirmed that he and other members of the Islamist regime ousted in 2019 have escaped from prison during recent fighting, raising new fears for a fragile ceasefire that has enabled foreigners to flee.

The 72-hour ceasefire brokered by the United States was already struggling to hold after the regular army launched renewed air strikes against rival paramilitary forces in the capital Khartoum late on Tuesday.

A ship carrying 1,687 civilians from more than 50 countries fleeing violence in Sudan docked in Saudi Arabia Wednesday, the foreign ministry said, the largest evacuation effort by the Gulf kingdom so far.

Saudi Arabia has received several rounds of evacuees by air and sea since fighting broke out in Africa's third-biggest country on April 15, part of what analysts describe as an effort to position itself as a major player in responding to regional crises.

As Sudan has descended into bloody chaos, hundreds of families have headed for Egypt on bumpy and harrowing 1,000-kilometre (600-mile) road trips through the desert, braving military checkpoints along the way.

Some of those who have made it across the Egyptian border to safety spoke of their fears as the cramped buses, with infants and elderly people on board, sped through the night along pitch-black and potholed roads.

They come in their tens of thousands by chartered plane, bus and even helicopter to the shrine of Hungary's "Miracle Rabbi" to pray for health, wealth and marriages for their children.

Once a year, orthodox Jews from all over the world descend on a sleepy Hungarian village in search of divine intervention.

Yeshaya Steiner, known as Rabbi Shayele, died in 1925 after devoting his life to feeding the poor and performing wonders for Jews and Gentiles alike in the tiny eastern village of Bodrogkeresztur.

Turkey on Tuesday detained 126 pro-Kurdish activists, journalists and lawyers in raids conducted just three weeks before a knife-edge vote that could extend President Recep Tayyip Erdogan's two-decade rule.

Police said their "counter-terror" operation was staged across 21 provinces, including Diyarbakir, the Kurdish minority's unofficial capital in Turkey.

State media said police held people suspected of financing the Kurdistan Workers' Party (PKK) or roping new members into the outlawed group.

Britain on Tuesday began evacuating its citizens from Sudan, after criticism of a delay in getting its passport holders out of the restive country.

"The first flight has left and you can expect that there will be at least two more flights overnight tonight," Prime Minister Rishi Sunak's official spokesman told reporters.

Britain only announced that it had launched a large-scale evacuation on Tuesday morning, lagging other countries and 10 days since fierce urban fighting erupted, leading to hundreds of deaths.

After paying nearly $100,000 in ransoms to free 10 family members, Khaled Taalou, a member of Iraq's Yazidi minority, is still working to free other missing relatives kidnapped by Islamic State group fighters.

Despite his efforts, five more relatives, along with thousands of other Yazidis, remain missing after being abducted by the jihadists.

"We are still looking. We do not lose hope," the 49-year-old said.