Iran has accused the Saudi-led coalition battling Shiite rebels in Yemen of hitting its embassy in the capital, Sanaa, in an overnight air strike.
The accusation comes amid a dangerous rise in tensions between Iran and Saudi Arabia in recent days, following the kingdom's execution of a Shiite cleric and attacks on Saudi diplomatic posts in the Islamic Republic.
Analysts have feared the dispute could boil over into the proxy wars between the two Mideast rivals in Yemen and in Syria.
Meanwhile, Saudi Arabia's eastern Shiite heartland prepared to hold a funeral service on Thursday night to honour the executed Shiite cleric, Nimr al-Nimr. That could spark further unrest, as witnesses in eastern Saudi towns have reported hearing gunfire overnight and armoured personnel carriers have been seen driving through neighbourhood streets.
On Thursday afternoon, Iran's state-run news agency said a Saudi-led air strike the previous night hit the Iranian embassy in Sanaa, citing Iran's Foreign Ministry spokesman. However, an Associated Press reporter who reached the site just after the announcement saw no visible damage to the building.
Saudi officials could not immediately be reached for comment.
The diplomatic stand-off between Iran and Saudi Arabia began on Saturday, when the kingdom executed Mr al-Nimr and 46 others convicted of terror charges - the largest mass execution it has carried out since 1980.
Mr al-Nimr was a staunch critic of the Saudi government and demanded greater rights for the kingdom's Shiite population, but always denied advocating violence. Saudi Arabia and its allies say Mr al-Nimr was found guilty of terrorism charges, and that condemnation of the execution amounts to meddling in Riyadh's internal affairs.
Iranian protesters responded by attacking the Saudi Embassy in Tehran and its consulate in Mashhad. Late on Sunday, Saudi Arabia announced it was severing relations with Iran because of the assaults. On Wednesday, Iranian diplomats in Saudi Arabia returned to Tehran, according to state media.
Since Saudi Arabia severed ties to Iran, a host of its allies have cut or reduced their ties as well.
On Thursday, Somalia joined Saudi allies such as Bahrain and Sudan and entirely cut diplomatic ties with Iran. The Somali Foreign Ministry said it recalled its acting ambassador to Tehran and ordered Iranian diplomats to leave Somalia within 72 hours.
In eastern Saudi Arabia, the home of Mr al-Nimr and much of the kingdom's roughly 10% to 15% Shiite population, three days of mourning over his death ended on Wednesday night. Mohammed al-Nimr, the sheikh's brother, said people planned to hold a funeral on Thursday for the cleric, although Saudi authorities already buried his corpse in an undisclosed cemetery.
There are concerns new unrest could erupt. Mr al-Nimr's brother, as well as another local resident of al-Awamiya in eastern Saudi Arabia, said they have heard gunfire on recent nights.
Meanwhile on Thursday, Iran banned the import of goods from Saudi Arabia over the tensions, according to a report by Iranian state television. It said the decision came during an emergency meeting of the Cabinet of President Hassan Rouhani.
In other developments, Saudi Foreign Minister Adel al-Jubeir arrived in Pakistan's capital, Islamabad, for meetings with Pakistani leaders. Pakistan, which is a predominantly Sunni Muslim state but has a large Shiite minority, has expressed hope that Saudi Arabia and Iran will be able to normalise their relations.
Saudi Arabia's deputy crown prince said he did not believe war would break out with Iran.
"It is something that we do not foresee at all, and whoever is pushing towards that is somebody who is not in their right mind," Mohammed bin Salman, the Saudi defence minister and 30-year-old son of King Salman, told The Economist magazine.
"Because a war between Saudi Arabia and Iran is the beginning of a major catastrophe in the region.... For sure we will not allow any such thing."
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