Supporters of a slain Tunisian opposition politician will gather for his funeral Saturday, after officials said he was gunned down with the same weapon used to kill a colleague, pointing at Al Qaeda links.
Already Friday, one person was killed during anti-government demonstrations triggered by the assassination of Mohamed Brahmi a day earlier, and the Islamist regime was gearing up for another day of tension.
Brahmi's widow Mbarka told AFP he would be buried Saturday at El Jallez cemetery in southern Tunis next to Chokri Belaid, the opposition politician assassinated in February.
Tens of thousands of people attended Belaid's funeral, when part of the procession turned into a protest against the ruling Islamist party Ennahda.
The families of both men have accused Ennahda of being implicated in the deaths, but the authorities said Friday that the investigation pointed to extremists.
Brahmi was killed with the same weapon used to gun down Belaid, Interior Minister Lotfi Ben Jeddou said.
"The first elements of the investigation show the implication of Boubaker Hakim, a Salafist extremist," said Jeddou.
Paris-born Hakim, 30, was a member of radical Sunni Muslim Salafist movement Ansar al-Sharia, which officials have previously linked to Al-Qaeda, he added.
Hakim was already wanted in Tunisia for kidnapping and arms trafficking, the minister said.
Public security chief Mustapha Taieb Ben Amor named 14 radical Islamist suspects -- including four behind bars -- implicated in the two political killings.
"The suspects are radical extremists, and some of them belong to Ansar al-Sharia," the main Salafist group in Tunisia, Ben Jeddou said.
Brahmi, 58, was gunned down outside his home in the Tunis suburb of Ariana by two gunmen.
He was an MP with the leftist and nationalist Popular Movement but quit the party he founded on July 7 saying it had been infiltrated by Islamists.
Saturday's funeral procession will start from the family home at 0900 GMT Saturday and travel 10 kilometres (six miles) to the cemetery, his widow said.
The interior ministry said it would deploy reinforcements to provide security as the General Union of Tunisian Labour (UGTT) called for a national funeral.
The UGTT called Friday's general strike in protest at "terrorism, violence and murders", while national airline Tunisair and some European carriers cancelled flights to Tunis.
But thousands of pro-government demonstrators also staged a solidarity rally in the capital.
The state prosecutor's office said an autopsy found that Brahmi had been hit by 14 bullets.
Balkis Brahmi, 19, one of Brahmi's five children, told AFP he had been killed by two men in black on a motorbike.
"At around midday, we heard gunfire and my father crying with pain. We rushed out -- my brother, mother and I -- to find his body riddled with bullets at the wheel of his car parked in front of the house," she said.
As news of the killing spread, angry protesters took to the streets in both Tunis and Sidi Bouzid, Brahmi's hometown.
And on Friday, one demonstrator died in the central town of Gafsa, after being hit on the head by a tear gas cannister fired by police.
Ennahda chief Rached Ghannouchi in a statement to AFP on Thursday said Brahmi's killing was a "catastrophe" for the country and said those responsible wanted to drag the country into civil war.
The presidency declared Friday a day of national mourning.
But political tension has been rising in Tunisia, with the launch of its own version of the Tamarod (rebellion) movement in Egypt that led to the ouster of Islamist president Mohamed Morsi on July 3.
After Brahmi's murder one party, Al Moubadara, decided to withdraw its five MPs from parliament, a party official said.
Adding to the Ennahda-led ruling coalition's worries, two parties decided to end cooperation in the work of the National Constituent Assembly (ANC) on a new constitution.
"Forty-two deputies have decided to withdraw from the ANC, as a first phase in a process aimed at... the fall of the government," Khemaies Ksila, a senior figure with the main opposition Nidaa Tounes party said late Friday.
Earlier, Beji Caid Essebsi, head of Nidaa Tounes, had said Ennahda was to blame for Brahmi's assassination because it had failed to identify Belaid's killers.
"There has not been any serious judicial action," he said.
The UN human rights office urged official restraint in the face of public anger.
"We urge the authorities in Tunisia to take great care not to inflame the situation further with excessive use of force and to respect the right of people to protest peacefully," spokesman Rupert Colville told reporters in Geneva.