The incident came hours after the announcement of the death of 56-year-old cleric Nimr al-Nimr, a key figure in anti-government protests in the kingdom since 2011. (Reuters Photo)
Angry crowds protesting at Saudi Arabia's execution of a top Shiite cleric hurled petrol bombs and stormed the kingdom's embassy in Tehran on Saturday before being cleared out by police, ISNA news agency reported.
The incident came hours after the announcement of the death of 56-year-old cleric Nimr al-Nimr, a key figure in anti-government protests in the kingdom since 2011.
The execution prompted strong condemnation from Shiite-majority Iran and Iraq.
Nimr, who spent more than a decade studying theology in Iran, was among a group of 47 Shiites and Sunnis executed Saturday on charges of terrorism.
Predominantly-Shiite Iran, the Sunni kingdom's longtime rival, said in reaction to Nimr's execution that "the Saudi government supports terrorist movements and extremists, but confronts domestic critics with oppression and execution."
It will "pay a high price for following these policies," foreign ministry spokesman Hossein Jaber Ansari warned.
In response, Saudi Arabia's foreign ministry said it had summoned Iran's envoy to protest the "aggressive Iranian statements on the legal sentences carried out today".
The Saudi interior ministry said the men had been convicted of adopting the radical "takfiri" ideology, joining "terrorist organisations" and implementing various "criminal plots".
An official list published included Sunnis convicted of involvement in Al-Qaeda attacks that killed Saudis and foreigners in 2003 and 2004.