Scanning the horizon with binoculars, Tunisian coastguard Islam Braiek is on the lookout for the growing number of migrants risking their lives crossing the Mediterranean to try to reach Europe.

With the modest means at Tunisia's disposal, it is no mean feat first to detect and then come to the rescue of migrants who get into difficulties, despite the improving weather conditions.

Migrants in Libya face "cruelty" and abuse, driving many people to risk their lives in dangerous Mediterranean crossings aimed at reaching sanctuary in Europe, Amnesty International said on Monday.

For years Libya has been a stepping stone for Africans seeking a better life in Europe. Syrian refugees fleeing the conflict at home are also making their way to Libya to try to reach the West.

The Jewish pilgrimage to Ghriba synagogue on the Tunisian island of Djerba is to take place Wednesday under extra security after the Bardo museum massacre and Israel's warning of terror threats.

Hundreds are expected to take part, unlike the thousands who flocked to Africa's oldest synagogue for the annual pilgrimage in the years before a 2002 suicide bombing claimed by Al-Qaeda that cost 21 lives.

Tunisia said Sunday security measures have already been taken to protect Jewish pilgrims at a religious festival next week on the island of Djerba, after Israel warned of "concrete threats."

Prime Minister Benjamin Netanyahu said on Saturday that Israel had learned of "concrete threats" of terror attacks against Jewish or Israeli targets in the North African country, prompting a quick denial from Tunis.

Prime Minister Benjamin Netanyahu said Saturday that Israel had learned of "concrete threats" of terror attacks against Jewish or Israeli targets in Tunisia.

The Tunisian government quickly denied the claims, saying no such threats existed.

Protesters took to the streets of Tunis Friday demanding to know the truth about the fate of two journalists whose execution-style killing in Libya was claimed by the Islamic State group.

"Give us back Sofiene; give us back Nadhir," the crowd of almost 200 demonstrators chanted as they brandished pictures of Sofiene Chourabi and Nadhir Ktari.

Tunisian fishermen rescued a group of around 80 migrants Friday after their boat got into difficulties while trying to sail from Libya to Europe, the Red Crescent told AFP.

"The flow (of illegal immigrants) does not seem to be stopping," said Mongi Slim, head of the Red Crescent in the southeastern port of Zarzis near the North African country's border with violence-plagued Libya.

Two Tunisian soldiers and 10 presumed jihadists have been killed in clashes in rugged terrain near the border with Algeria this week, the defense ministry said on Friday.

"Another two soldiers have been martyred and seven wounded in this army operation on Mount Salloum," spokesman Belhassen Oueslati told AFP.

More than 30 percent of young Arabs are jobless because of unrest in many Arab nations and not enough investment, a top labor official said on Sunday.

"The unemployment rate among Arab youth until the age of 30 years exceeds 30 percent," the director general of the Arab Labor Organization Ahmad Mohammed Luqman told AFP.

Tunisian authorities have released a blogger handed six months in prison for defaming the army, after he served more than half his sentence, his brother said Friday.

Yassine Ayari was prosecuted over blogs he wrote alleging financial abuses by army officers and defense ministry officials in a case Human Rights Watch described as "not worthy of the new Tunisia".