A supporter of the Nidaa Tounes party dances in front of the party’s headquarters, in Tunis. Tensions between two wings of Nidaa Tounes, whose name means Call of Tunis, spilled over into violence last week when a party meeting descended into open fighting with fists and sticks. A split within Nidaa Tounes could trigger political instability in the country that launched the first of the Arab Spring revolutions in 2011.

Rival ambitions, insults and accusations of violence have brought Tunisia’s ruling party to the brink of collapse as the country struggles to lead the way toward a post-Arab Spring democracy.

The secularist Nidaa Tounes party was already weakened by the departure of its leader Beji Caid Essebsi, in line with the constitution after he was elected president last December.

It has now been riven for months by bad blood between its secretary general, Mohsen Marzouk, and the president’s son Hafedh Caid Essebsi, in what insiders are calling a “battle for succession”.

The rivalry threatens to tear apart the government in a country held up as a rare success story for the Arab Spring after its 2011 overthrow of longtime dictator Zine El Abidine Ben Ali.

On Sunday, the bitterness reached new heights with alleged violence during a meeting of Nidaa’s executive committee in Hammamet, 60 km from the capital.

Footage widely shared on the Internet shows a group of people armed with sticks — allegedly Essebsi supporters — blocking the entrance to the venue and hitting people trying to enter.

Several pro-Marzouk committee members charged that this amounted to “fascist aggression” orchestrated by “certain leaders of the party” intent on seizing control of it.

“Such violence threatens the democratic process,” one member, Bochra Belhaj Hmida, told AFP.

As a loose alliance of leftist and center-right figures together with former officials of Ben Ali’s regime, Nidaa Tounes has survived past internal crises.

But a key party congress has been delayed for several months, as protests are voiced over the ambitions of the 88-year-old president’s son, who is in his early 50s.

Resigning last month from his post as minister in charge of relations with parliament, party member Lazhar Akremi warned that the president may be trying to set up a dynasty. “We’ve said no to hereditary power, no to the return of the old regime,” he said at the time.

Tunisian media this week warned of an impending implosion, with La Presse newspaper saying Nidaa had reached “the point of no return” and magazine Leaders saying “the break is complete”.

The president has not been spared the flak. When he resigned, Akremi accused Essebsi of having abandoned his political party for the comforts of the presidential palace in Carthage.

“He left the boat to jump on a yacht. It’s inexcusable,” Akremi said. On Sunday, 32 legislators who support the 50-year-old Marzouk sent an open letter accusing the president of standing “passively” on the sidelines and failing to help resolve the crisis.

Essebsi’s spokesman Moez Sinaoui said the president did not intend to take sides, although he later received a delegation of lawmakers.

Executive committee member Chokri Mamoghli said the intervention had come too late.

“Nidaa is dead,” he said on his Facebook page. “The government will probably fall.”

The crisis has hobbled the government of Prime Minister Habib Essid, whose economic performance has drawn fire even from within the ruling party. La Presse said the Essid government lacked any “vision of economic and social development” for the future of Tunisia, despite its announcement of a five-year development plan.

The paralysis could present an opportunity for the moderate Islamist movement Ennahda, which had a disappointing post-revolutionary spell in power but was defeated in the last election and joined a Nidaa-led coalition.

Ennahda chief Rached Ghannouchi said on Tuesday the party was not seeking to take advantage of the divisions in Nidaa.

“We have no plan whatsoever to seize power or to run the government,” he said.

For now at least, political scientist Ahmed Manai said, the crisis had not moved beyond internal party politics.

“I don’t think this will lead to the collapse of the government,” he said. “It’s in everybody’s interest for it to continue and for there not to be a political vacuum, including that of Ennahda.”

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