TUNIS // They are scenes that Tunisians long to see relegated to the past: police chasing down protesters; stone-throwing youths ransacking neighbourhoods.
Yet those scenes have gripped Avenue Habib Bourguiba, the Tunisian capital's central promenade, and surrounding streets for the past four days. On Saturday night the government imposed a curfew in greater Tunis.
Avenue Habib Bourguiba, with its shops, cafes and double-row of manicured ficus trees running down a median, has become the main stage for street politics since Tunisia's president was deposed in January.
Some protests have gone ahead unhindered while others have been crushed by the police. Meanwhile, for every impassioned demonstrator is a weary merchant impatient for stability.
Montasser Jomni, who runs a cafe on the avenue with his wife, Meriem, said: "It's frustrating: one moment people are on the terrace enjoying themselves, the next there's a demonstration and then police everywhere."
It was Friday evening and the avenue was tense after police used tear gas to disperse anti-government protesters. In one police van, several policemen appeared to be pummelling someone with batons.
"Whenever it kicks off, you have to pull in your tables and chairs, and sometimes close entirely," Mr Jomni said. "In the past two days we've lost at least 800 dinars. Many of our neighbours have lost more."
Anti-government protests erupted on Thursday after Farhat Rajhi, a former interior minister in the interim government, said in videotaped remarks posted on Facebook that victory in legislative elections in July by the Islamist Nahda party would provoke a military coup.
Mr Rajhi has since called his remarks hypothetical and said he was filmed at unawares, while the government has denounced his utterances. Protesters nevertheless flooded Avenue Habib Bourguiba on Thursday, accusing the government of failing to safeguard Tunisia's revolution.
The avenue began life as the unpaved Avenue de la Marine, muddy in winter and dusty in summer, the main street of France's colonial extension of Tunis in the late 19th century. In 1900 it was renamed for Jules Ferry, a French minister and enthusiastic imperialist.
When Tunisia gained independence in 1956, a statue of Ferry was pulled down and the avenue was renamed for Habib Bourguiba, modern Tunisia's first president.
Today colonial edifices are joined by additions such as the towering Hotel Africa and the interior ministry where, on January 14, thousands gathered in protests that toppled Bourguiba's successor, Zine el Abidine Ben Ali.
The avenue became a carnival of marches and impromptu speeches as Tunisians revelled in free expression after decades of authoritarian rule. One man held dozens enthralled one afternoon with a litany of grievances, punctuating each with the phrase, "w haja okhra!" - "and another thing!"
Since then, protesters bent on purging the politics of former Ben Ali loyalists have helped force several cabinet reshuffles. Conservative Muslims have marched to demand that Ben Ali-era restrictions on the headscarf be lifted.
Police have sometimes responded with tear gas and batons, and have clashed with gangs of stone-throwing young men who have appeared after some of the protests. On Thursday, several hundred protesters gathered in front of the interior ministry.
"An officer told them through a bullhorn to let businesses operate normally," said Meriem Jomni, Mr Jomni's wife. "But it didn't work."
According to the Associated Press, police then fired tear gas to disperse protesters and beat up AP photographer Hassene Dridi, who was covering the protest.
On Friday, protesters returned to the avenue. Police charged with tear gas and batons, also attacking bystanders and reporters, said Agence France-Presse.
AFP photographer Fathi Belaid was among 15 media workers assaulted by police on Friday, according to a statement by Tunisia's journalists union. The interior ministry issued an apology on Friday to "journalists and citizens involuntarily assaulted" and promised to investigate the attacks.
On Saturday police again dispersed protesters in Avenue Habib Bourguiba with tear gas but showed more restraint than on previous days, according to newswire services. Later in the day, police clashed with stone-throwing young men who emerged from adjacent neighbourhoods.
"These are just hooligans trying to spread instability," said one masked riot policeman who identified himself as Mounir, one of a group of policemen facing off against several dozen young men in a narrow side street.
A moment later a stone sailed towards the policemen, who responded by firing several tear-gas canisters.
The young men and policemen traded stones and tear gas for more than an hour before the youths vanished.
On Sunday police once again used tear-gas to drive protesters off Avenue Habib Bourguiba, according to Reuters news agency. Meanwhile, merchants are grumbling over what they describe as a disruptive cycle of street demonstrations and police crackdowns.
"Around 30 police barged in here earlier," said Yousef, a cafe head waiter who did not give his surname, speaking on Friday afternoon. "Many employees and their families depend on this cafe, and now we're going to be closed over the weekend."
Further along the avenue, Mr Jomni was looking gloomily at his half-empty tables on Friday from behind a newly installed ice cream case. "We're tired," said Mrs Jomni beside him. "We're trying to build our business, step by step, and then all at once."
