Violent protests left one man dead early Saturday in the southern Tunisian city of Gafsa, two days after the assassination of a secular opposition figure. It was the first death in protests since demonstrations over the assassination of Mohamed Bahmi began on Thursday.
Eyewitness accounts conflicted on how the protestor died. Thousands of anti-government protesters also massed in the capital on Friday, while shops and banks closed their doors and all flights in and out of the country were canceled.
Secular opposition politician Mohamed Brahmi was killed on Thursday with the same gun that was used to kill his coalition party leader Chokri Belaid six months ago, Tunisia's interior minister said, adding to suspicion that a hardline Islamic group that has been a vociferous critic of the country's secular groups was behind the attack.
"The same 9mm automatic weapon that killed Belaid also killed Brahmi," Lofti Ben Jeddou told a news conference on Friday, saying that it suggested a continuity of involvement from the same Salafist group.
He named the main suspect as hardline Salafist group Boubacar Hakim, which is already being sought on suspicion of smuggling weapons from Libya.
Ben Jeddou said that ballistic examination of the bullets fired on July 25 at Brahmi showed they came from the same gun used to kill leftist Belaid in February.
Two men on a moped shot Brahmi 14 times in front of his home as he was getting in his car.
"He was riddled with bullets in front of his wife and children," said Mohsen Nabti, a fellow member of the small leftist movement, in a tearful account on Tunisian radio.
Belaid was killed in similar fashion.
Tunisian unions called a general strike on Friday after Brahmi’s assassination, prompting thousands to take to the streets to protest and sparking international condemnation.
Shops and banks were closed and the country's national airline Tunisair canceled all flights, as the General Union of Tunisian Labour (UGTT) called for the nationwide strike in protest against "terrorism, violence and murders" on a day that also served as a national day of mourning.
Al Jazeera's Youssef Gaiga, reporting from Tunis, said that people were shocked by the assassination, which came during the celebration of the day when the Tunisian republic was announced and constituted.
"There are already people protesting right now in front of the general union in Tunis and going out to the main street," Gaiga said.
The ruling Ennahda party, a moderate Islamist group, denied accusations from the victim’s family that it was involved in the murder of member of the People Movement Party, which is part of the same coalition as Chokri Belaid, who was assassinated in February.
The UGTT last called a two-hour general strike on January 14, 2011, the day former Tunisian leader Zine El Abidine Ben Ali fell.
Navi Pillay, the UN human rights chief, condemned the killing of Brahmi and demanded an investigation into his slaying.
"I am shocked and deeply saddened by the news of Mr. Brahmi's assassination. I call upon the authorities to immediately launch a prompt and transparent investigation to ensure that the people who carried out this crime are held accountable," Pillay said in a statement.
The slain politician's widow, Mbarka Brahmi, told the Reuters news agency "this criminal gang has killed the free voice of Brahmi," without specifying who she thought was behind the shooting.
Brahmi's sister, Souhiba, meanwhile, accused the main Islamist Ennahda party of being behind the killing.
"Ennahda killed my brother," she said. Ennahda has condemned the murder.
In the southern town of Sidi Bouzid, the cradle of the Tunisian revolution where Brahmi is also from, protesters set fire to two local Ennahda party offices, witnesses told Reuters.
"Thousands have taken to the streets. People have blocked roads and set tires alight," said Mehdi Horchani, a resident of Sidi Bouzid. "People are very angry."
On Wednesday, Noureddin B'Hiri, senior adviser to the prime minister, said that six people believed to have orchestrated the killing of Belaid more than five months ago had been identified.
"We have identified the sponsors and the authors of the assassination of Chokri Belaid," B'Hiri said after a cabinet meeting.
B'Hiri had said that the details would be revealed "soon" by Interior Minister Jeddou, without saying when.
Belaid was shot dead outside his home on February 6, in an attack that shocked Tunisians and led to a political crisis that brought down the government of Prime Minister Hamadi Jebali.
The interior ministry blamed the killing of Belaid, who was an outspoken critic of Jebali's ruling Ennahda party, on a cell of "radical Islamists".
In April, the government released the photos and names of five suspects and appealed for help in arresting them.
Since the revolution that toppled Ben Ali in January 2011, "hardline Islamists" have been blamed for numerous acts of violence, notably an attack on the US embassy last September that left four assailants dead and the killing of Belaid.
Brahmi and Belaid were both very critical of the ruling Ennahda Party.
Brahmi's family said his funeral would take place on Saturday and he would be buried near the tomb of Belaid.
Tunisian President Moncef Marzouki asked the army to organize a state funeral for Brahmi, the presidency said.
Al Jazeera and wire services