As the British prime minister, David Cameron, visited Riyadh in mid-January, wooing Saudi business and strengthening bilateral relations, a young Shia man in the eastern province was shot dead.

Following the kingdom's huge arms deal with the United States, Cameron apparently wanted to persuade the Saudis to buy Typhoon Eurofighters. His visit was a slap in the face for protesters, who are demanding human rights and more of a say in their country's affairs.

In the week beginning 16 January thousands of people – activists say tens of thousands – took to the streets of Awwamiya in the eastern province to commemorate the death of Issam Muhammad Abu Abdallah, aged 22. He had been shot by Saudi security forces on the night of 12 January.

According to the interior ministry, the security forces were defending themselves after a police car had been attacked. Activists and local Shia news websites acknowledge that the police were attacked, but argue that the police used force indiscriminately. Issam's funeral turned into a large rally at which emotions ran high and anti-government slogans were chanted.

These events are just the latest episodes in one of the Middle East's most under-reported conflicts. Last year, Shia citizens in the eastern province took to the streets just days after the uprising started in neighbouring Bahrain on 14 February. Their protests were largely peaceful and they were hoping that Saudis in other areas would join them on a planned "day of rage" in March.

This day passed without major demonstrations, even in Shia areas, as the Shia protesters had allegedly been told their grievances would be addressed if they stayed at home. Those promises were never fulfilled, however, and the state chose to arrest the leaders of the demonstrations over the summer, further inflaming the situation.

Instead of using such repression, the regime should have addressed the grievances of the protesters, including the release of political prisoners. The Saudi Shia minority, mainly located in the eastern province, has long complained of discrimination in government employment and business, as well as restriction of religious practices. Initially, the protesters were not calling for the downfall of the monarchy but as repression intensified (demonstrations are illegal in Saudi Arabia) some did and also started attacking the security forces.

In October, shootings were reported between security forces and armed men outside a police station in Awwamiya. The town, which has for decades been a hotspot of Shia opposition, has since been in a virtual state of lockdown, and now seems to have started an uprising – the "intifada of dignity", as activists have called it.

Weekly and sometimes daily protests occurred in the villages of Qatif governorate and in late November and early December the first Shia were killed. When four young Shia were shot dead over the course of a few days, their funerals turned into the biggest demonstrations the eastern province had witnessed in three decades. The spiral of protest, killings and burials that was so crucial in galvanising protest in other countries such as Syria and Bahrain was set in motion. Particularly in a rural and suburban context, most people in a neighbourhood will know the deceased and therefore come out to his burial.

The Saudi regime seems prepared to crush these protests with an iron fist. It does not want to concede to Shia demands out of fear that other constituencies and regions might present similar demands. But this seems a very short-sighted strategy, as evidence from other Arab uprisings suggests. Online activists have already developed a mythology around the five "martyrs" and if there are more, this will probably galvanise protests rather than stifle them.

In addition, Awwamiya boasts a cleric who has taken the lead in this uprising and speaks bluntly against the government. Nimr al-Nimr was long a peripheral figure in the local Shia power struggle but now seems to have become the most popular Saudi Shia cleric among local youth. He denounced a list of 23 wanted Shia protesters that was issued by the interior ministry earlier this month. Although some have since turned themselves in or been arrested, most are still in hiding.

Meanwhile, several hundred residents of Awwamiya have signed a petition demanding an independent investigation into the recent shootings. Findings of an earlier promised investigation into the four deaths were not published. There is also a danger that the protesters will use violence as a tactic when they do not see any gains from peaceful protests. On 14 January, a police car in Qatif was shot at, injuring some policemen. Although it is not clear that these incidents are connected, weapons abound in the kingdom.

The Saudi regime is playing with fire and its western backers are standing by idly. But it would be in the interest of all parties if the regime made major concessions, not only to its Shia citizens but to the rest of the population. For western countries, the more people are killed the more difficult it will be to defend the strategic alliance with Saudi Arabia.

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