The former prime minister of Iraq, Nuri al-Maliki, has said that the execution of the prominent Shi'ite cleric Sheikh Nimr al-Nimr by Saudi Arabia will be the downfall of the Gulf kingdom's government.

Mr al-Maliki, who was prime minister of Iraq between 2006 and 2014, said in a statement that his countrymen "strongly condemn these detestable sectarian practices and affirm that the crime of executing Sheikh al-Nimr will topple the Saudi regime as the crime of executing the martyr al-Sadr did to Saddam," referencing the death of another prominent cleric in Iraq in 1980.

Hundreds of armoured vehicles were sent to Qatif in Saudi Arabia to contain protests in response to the execution, while demonstrators in Bahrain have been tear-gassed.

Several protests have taken place in majority Shia Qatif and in Bahrain, following the execution of Sheikh al-Nimr and 46 others for ‘terrorism offences’.

Demonstrators carrying pictures of the Shi’ite cleric were involved in a clash with police in the Bahraini village of Abu-Saiba, where dozens were tear-gassed, according to witnesses.

It is feared that the death of the outspoken cleric will exacerbate tensions in the region, with activists calling for further protests in Bahrain, and several demonstrations breaking out in Saudi Arabia’s Eastern Province.

A Bahriani protester holds up a picture of Nimr al-Nimr after his execution

Armoured vehicles have been seen entering Qatif, with resistance groups in the area calling for people to join the protests against the execution of Sheikh al-Nimr, who had much popular support in the Shia community.

Protesters clash with security services in Bahrain (EPA)

Security forces in other Shia-populated areas are also said to be on high alert, while many police stations and security posts have been closed following al-Nimr’s execution in case of repercussions from Saudi Arabia’s Shia community.

However, al-Nimr’s brother Mohammed al-Nimr has asked that any reaction to the execution be peaceful.

Juveniles on death row in Saudi Arabia Show all 8 1 /8 Juveniles on death row in Saudi Arabia Juveniles on death row in Saudi Arabia Abdullah al-Zaher Abdullah al-Zaher was arrested at the age of 15 for attending a protest and he is was the youngest in a group of juvenile offenders put on death row Juveniles on death row in Saudi Arabia Abdullah al-Zaher Previously held alongside fellow juvenile offender Ali al-Nimr, whose case sparked outrage around the world, Abdullah has now been moved to solitary confinement at a new facility and could be beheaded at any moment Juveniles on death row in Saudi Arabia Abdullah al-Zaher His family and lawyers believe he was forced to sign a document without knowing its contents, and which later was used as a “confession” in the closed trial against him Juveniles on death row in Saudi Arabia Ali Mohammed al-Nimr Ali Mohammed al-Nimr faces imminent beheading and crucifixion for crimes he reportedly committed as a child Juveniles on death row in Saudi Arabia Ali Mohammed al-Nimr The UN has issued an urgent call for Saudi Arabia to halt his execution but a Saudi court has upheld the sentence of Ali Mohammed al-Nimr, the son of a prominent government dissident, despite growing and high-level international condemnation Juveniles on death row in Saudi Arabia Ali Mohammed al-Nimr Mr al-Nimr, who was arrested in 2012 for his participation in Arab Spring protests when he was just 16 or 17 years old, could now be put to death at any time Juveniles on death row in Saudi Arabia Dawood al-Marhoon Dawood al-Marhoon was 17 year old when he was arrested for participating in an anti-government protest Juveniles on death row in Saudi Arabia Dawood al-Marhoon After refusing to spy on his fellow protesters, he was tortured and forced to sign a blank document that would later contain his ‘confession’. At Dawood’s trial, the prosecution requested death by crucifixion while refusing him a lawyer

He told Reuters: “Sheikh Nimr enjoyed high esteem in his community and within Muslim society in general and no doubt there will be reaction.

Protests follow execution