A Tunisian jailed for posting caricatures of Prophet Mohammed online is to remain in prison despite a presidential pardon, pending a separate trial for "embezzlement", his lawyer said Thursday.

"I contacted the judge investigating the case at the court in Mahdia who confirmed the embezzlement charges relating to when Jabeur (Mejri) worked for the SNCFT (Tunisian railways)," Ahmed Mselmi told AFP.

A Tunisian jailed for posting caricatures of the Muslim Prophet Mohammed online has received a pardon from President Moncef Marzouki, his spokesman said Wednesday, but it is unclear whether he will be released.

"A presidential pardon for Jabeur Mejri has been issued for the case in which he was condemned to nearly eight years" in prison, spokesman Adnene Manser told Shems FM radio.

U.S. Secretary of State John Kerry made an unannounced trip to Tunisia on Tuesday to back the transition to democracy in the North African country that spawned the Arab Spring.

His visit came amid troubled relations between the United States and longtime ally Egypt over the military overthrow of the government elected in the aftermath of the 2011 uprisings that shook the Arab world.

More than a thousand protesters gathered on Monday in the Tunisian town of Jendouba to condemn the weekend killings of four people by suspected Islamist militants.

As the four victims were buried, new Prime Minister Mehdi Jomaa said the state would not be undermined by "terrorism."

More than a thousand protesters gathered on Monday in the Tunisian town of Jendouba to condemn the weekend killings of four people by suspected Islamist militants.

"Tunisia is free, terrorism out," and "Faithful to our martyrs," were among the slogans chanted by the protesters outside the governor's office in the town in northwestern Tunisia, before marching down the main street, Agence France Presse reported.

Jihadists shot dead two people in a car they stopped at a roadblock near Roman ruins in Tunisia and two policemen who later sped to the scene, the interior ministry said Sunday.

The killings occurred on Saturday night in the Jendouba area of western Tunisia near Bulla Regia, the site of historic Roman ruins, it said in a statement.

Tunisian authorities said Friday they will tighten checks on people wearing the Muslim full-face veil, as part of efforts to combat Islamist violence, claiming the cover was being used by fugitives.

"The interior ministry announces that it will strengthen checks on everyone wearing the niqab," or the veil, the ministry said on its official Facebook page.

The trial of two Tunisian policemen on charges of raping a young woman in 2012 resumed behind closed doors on Thursday, after repeated delays described by the victim as an "ordeal."

"It's a case that touches on moral issues, we ask everyone present to leave the room," the judge said as the hearing began.

Tunisia's new constitution, adopted in late January after two years of acrimonious debate, started coming into effect on Monday when it was published in the official journal.

The country's leaders signed the charter at the end of last month, three years after the uprising that toppled longtime dictator Zine El Abidine Ben Ali and ignited the Arab Spring.

Progressive Socialist Party leader MP Walid Jumblat on Monday warned that Lebanon will further “drown” in terrorist bombings unless the “Lebanese brain” acts and innovates solutions.

Jumblat lauded “the rational call voiced by Ms. Rabab al-Sadr, the sister of missing imam Sayyed Moussa al-Sadr, in which she expressed a responsible stance, reminding of landmark remarks that were launched by the imam in 1976, through which he addressed the Lebanese brain.”