The latest crisis between regional rivals Iran and Saudi Arabia deepened Tuesday, four days after it erupted with the execution of Shiite cleric Sheikh Nimr al-Nimr.
A snapshot of events so far:
Riyadh announces the execution of Nimr, 56, who had voiced bitter opposition to the Saudi royal family, and 46 other "terrorists."
Demonstrators rally in Qatif, eastern Saudi Arabia, where most of the Shiite minority live. Nimr was arrested in 2012, three years after calling for Eastern Province's Qatif and Al-Ihsaa governorates to be separated from Saudi Arabia and unite with Bahrain.
Tehran warns that Riyadh would "pay a high price" for the execution, but the Saudis call Iran "a state that sponsors terror."
Diplomatic envoys from both countries are recalled.
Gulf monarchies express support for Saudi Arabia, in particular Bahrain which faces chronic unrest among its Shiite minority, and where police use tear gas to disperse demonstrators.
Indignation floods the Shiite world. In Iraq, hundreds demonstrate in the holy Shiite city of Karbala and prominent Shiite lawmaker Khalaf Abdelsamad calls for the closure of Riyadh's newly reopened embassy in Baghdad after a 25-year hiatus.
In Tehran, hundreds of demonstrators set fire to the Saudi embassy and police make 40 arrests. In Mashhad, northeastern Iran, four are arrested after a crowd torches a Saudi consulate.
Iran's supreme leader Ayatollah Ali Khamenei warns that Saudi Arabia will face "divine revenge" for executing Nimr. President Hassan Rouhani denounces attacks on the Saudi embassy and consulate as "totally unjustifiable."
Hezbollah chief Hassan Nasrallah slams the Riyadh government as "criminal and terrorist." "This is not something we can ignore," he warns.
Thousands of Shiites demonstrate in Pakistan and violence breaks out in Bahrain and Indian Kashmir.
Saudi Arabia announces the rupture of diplomatic relations with Iran and gives Tehran's diplomats 48 hours to leave.
Iran accuses Riyadh of seeking to stoke regional tensions.
Thousands of supporters of prominent Iraqi Shiite cleric Moqtada al-Sadr protest to demand that Baghdad sever ties with Riyadh. Blasts rock two Sunni mosques in central Iraq killing one man, while a muezzin is gunned down south of Baghdad.
Bahrain and Sudan cut diplomatic ties with Iran and the United Arab Emirates downgrades its relations.
In Tehran, 3,000 people protest against the Saudi royal family, and burn Israeli and US flags.
Saudi Arabia cuts all air links with Iran.
Russia offers to mediate and US Secretary of State John Kerry calls both countries' foreign ministers to urge calm.
Riyadh says the crisis should not affect peace efforts in Syria and Yemen.
A UN Security Council statement strongly condemns the attack on the Saudi embassy in Tehran but makes no mention of Nimr's execution.
Iran says Saudi Arabia's severance of diplomatic relations will not hurt it or damage its development.
Iranian President Rouhani says Saudi Arabia should not respond to criticism of its regime by beheading people.
Kuwait recalls its ambassador to Tehran, the fifth Arab country to cut or downgrade relations with Iran.
UN Syria peace envoy Staffan de Mistura holds talks in Saudi Arabia before a visit to Iran.
Turkey says it is ready to help calm tensions.
The six-nation Gulf Cooperation Council, of which only Oman has not yet reacted, calls a foreign ministers' meeting for Saturday, a day before an Arab League meeting in Cairo. – Rappler.com