Supporters of the Sunni preacher Ahmed al-Assir (pictured) gathered across Lebanon on June 28th, some brandishing weapons. Until this week most Lebanese viewed the sheikh mainly as an oddball. Before the start of the civil war in neighbouring Syria, he was unknown beyond his hometown of the southern port city of Sidon. But he rose to prominence through fiery sermons bashing Syria’s president, Bashar Assad, and Hizbullah, the Lebanese Shia party-cum-militia which backs him. Mr Assir’s political stands—such as a sit-in Sidon for 35 days last July to protest against Hizbullah’s weapons—were overshadowed by more amusing stunts, like his trip to a local ski resort in January and the conversion of pop star Fadl Shaker into one of his Salafist followers.

That changed this week when Mr Assir’s gunmen clashed with the Lebanese army for two days after killing three soldiers at a checkpoint in Sidon, leaving 46 dead and the sheikh on the run. Tensions in Lebanon are intensifying along the Sunni-Shia fault lines that reflect the opposing sides in the war next door. But Mr Assir, whom many Sunnis abhor for his radicalism, represents more than sectarian fallout from Syria. For many Sunnis, Mr Assir’s confrontation with one of Lebanon’s state institution was a red line—“I supported him until now but the army is different,” said a man in Sidon who spoke on condition of anonymity. Yet it is a sign of the deepening rift in Lebanon between the Sunni community and the army. During the clashes, Mr Assir, who dismisses Lebanon’s soldiers as Iranian and Shia stooges, called on “Sunnis and non-Sunnis to leave the army immediately”. 

Since Lebanon’s 15-year civil war ended in 1990, the fractious state—home to 4m people and 18 confessions—has been governed by a complex set of rules that distributes power between the sects, which are roughly equally distributed under the broader categories of Sunni, Shia and Christian. Parliamentary seats are set aside for different religious groupings, while the troika of prime minister, president and speaker must be Sunni, Christian and Shia respectively. But having splintered along sectarian lines during the war, the army in more recent times has stood out as one of the few Lebanese institutions to rise above sectarian divisions and secure the backing of the majority of society. America has helped bolster the forces with millions of dollars of military aid since 2005, with the aim of enabling the army to crack down on Sunni militants and counter-balance Hizbullah, which acts as a de facto army in some areas of Lebanon and fought a war with Israel in 2006.

Yet since Hizbullah’s inclusion in Lebanon's government in 2008, the group’s influence on state institutions, including the army, has grown, feeding Sunni worries. Today many Sunnis accuse the army of cracking down disproportionately on Sunni militants, while Shia militias such as Hizbullah remain armed. Reports that Hizbullah fighters helped the army in Sidon did little to boost its neutral image. This anger and fear over a lack of representation, armed or otherwise, of the Sunni community helped Mr Assir build his following. Many see Mr Assir's rise as part of increased Sunni militancy in Lebanon, inspired in part by Syria’s co-religionist rebels, but also by a sense that no one else will defend their interests.

The clashes in Sidon have added to a general sense of growing instability in Lebanon. Politicians are still struggling to form a new cabinet since the last one resigned on March 22nd. The country has proved resilient, but since Hizbullah intervened in Syria’s war, openly fighting alongside Mr Assad for the first time earlier this month, Syria’s rebels have increasingly fired shells into eastern Lebanon. Clashes and gun battles, long a feature of life in Lebanon, have become more frequent. The sheikh provides little cause for amusement now.