Six policemen killed by suspected jihadists were buried Thursday as anti-government sentiment mounted and fresh doubts arose over long-awaited talks to end the political paralysis gripping Tunisia.
Protesters attacked two offices of the ruling Islamist party, amid rising anger at Ennahda's failure to stem the deadly violence caused by extremists.
President Moncef Marzouki declared three days of national mourning for the slain National Guards, but the victims' families barred representatives of the Islamist-led government from attending the funerals, which drew angry crowds.
In Beja, west of the capital, hundreds of protesters attacked the Ennahda office, throwing rocks and petrol bombs, after a policeman killed by jihadists on Wednesday evening was buried there, party representative Abdessatar Amdouni told local radio.
Five Ennahda members were injured in the attack in Beja, where violence last week left two soldiers and nine suspected Islamists dead.
Early on Thursday, protesters torched the Ennahda office in Kef, before another slain guardsmen was laid to rest, an AFP photographer reported.
At the funeral, marchers behind the coffin shouted anti-Islamist slogans, including (Rachid) "Ghannouchi assassin," referring to Ennahda's veteran leader.
General strikes called by the powerful UGTT trade union confederation were observed in two regions of the country, including Sidi Bouzid, where Wednesday's clash broke out and where the uprising that toppled strongman Zine El Abidine Ben Ali in 2011 first began.
"We have rejected plans by the government, the politicians to pay homage... We reject their condolences, their presence and above all the presence of (Prime Minister) Ali Larayedh," said Jamel Salhi, the brother of one of the victims, in Sidi Bouzid.
Since Ben Ali's overthrow, Tunisia has been rocked by waves of violence blamed on militant Islamists, notably a deadly attack on the US embassy last year and the murder of two opposition politicians, which have plunged the country into crisis.
Opposition mistrust persists
Negotiations between the Islamists and opposition, the centrepiece of a roadmap to end the impasse, ran into fresh trouble on Thursday after the premier gave what the opposition described as an "ambiguous" commitment to step down.
"We repeat today our commitment to the principle of relinquishing power in line with the different phases envisaged in the roadmap," Larayedh in a heavily delayed speech late on Wednesday that was supposed to precede the start of the talks.
But his promise to resign was not good enough for the Popular Front, a group of leftist opposition parties, or Nidaa Tounes, headed by ex-premier Beji Caid Essebsi, an outspoken critic of the Islamists.
UGTT chief Houcine Abassi said the premier needed to clarify his comments to get the national dialogue back on track, and rescheduled the launch of the dialogue for 0900 GMT on Friday.
The opposition has been demanding a "clear commitment" by Larayedh to resign within three weeks, as stipulated in the roadmap drawn up by mediators and agreed to by Ennahda, to allow negotiations to begin.
According to the roadmap, the talks must lead within three weeks to the formation of a caretaker cabinet of technocrats.
Negotiators will also have one month to adopt a new constitution, electoral laws and a timetable for fresh elections -- key milestones in a transition that has effectively been blocked by bitter differences between the government and the opposition.
Commenting on the latest violence, Larayedh insisted Tunisia was "in the process of defeating terrorism... despite the sacrifices," and that the security forces were pursuing the remaining militants.
In addition to the six policemen and one militant killed in Sidi Bouzid, another policeman was killed in the northern town of Menzel Bourguiba on Wednesday.
The government has admitted it lacks the resources to combat militant groups and has struggled to contain them.
The interior ministry said 11 militant Salafists were arrested in Menzel Bourguiba on Wednesday evening.
It also said a car bomb "ready to explode" was found at the site of Wednesday's clashes in Sidi Bouzid, and claimed to have established links between the jihadists there and the militants who carried out the deadly attack in Beja last week.