The Islamic State jihadist group Saturday demolished a prison in the Syrian city of Palmyra, a monitor said, eliminating what was for decades one of the country's most feared detention centers.

The jail was "largely destroyed after IS planted explosives inside and around it", 10 days after the jihadists seized Palmyra from regime forces, the Syrian Observatory for Human Rights said.  

The Islamic State jihadist group launched an assault on the largely Kurdish city of Hasakeh in northeast Syria on Saturday, the Syrian Observatory for Human Rights said. 

The attack came a day after Kurdish militia executed 20 civilians accused of supporting the extremists, the monitoring group said.

The General Directorate of State Security raided two towns of the Bekaa Valley, detaining two suspects for allegedly belonging to the Islamic State of Iraq and the Levant (ISIL).

The state-run National News agency reported, that a state security unit raided the town of Tamnin near Niha and the village of Bednayel, arresting two Syrian nationals, who have links to ISIL.

Barrel bombs dropped from regime helicopters killed at least 71 civilians in Syria's Aleppo province Saturday, after forces loyal to President Bashar Assad retreated from the neighboring northwestern region of Idlib.

The Syrian Observatory for Human Rights said "at least 71 civilians were killed, and dozens were wounded, when regime helicopters dropped barrel bombs on the city of Al-Bab and in Al-Shaar in east Aleppo city".

The U.S. Department of State renewed its travel warning advisory to Lebanon over safety and security concerns, citing fears over the increasing tension along Lebanon's northeastern border town of Arsal and the rise of terror groups in the country.

U.S. Embassy sources informed Naharnet on Saturday that “the travel warning, which is renewed every six months, is issued to provide U.S. citizens in Lebanon with more concrete context on the risks” of traveling or residing in Beirut.

A growing number of extremist groups from Africa to southeast Asia are shifting their allegiance to the Islamic State group, leading to greater risks for "cross-pollination" among conflicts beyond Syria and Iraq, the head of Interpol said Friday.

Juergen Stock cited this shift as an emerging trend at a U.N. Security Council meeting along with changing travel methods being used by foreign fighters seeking to join groups like the Islamic State and al-Qaida.

A revised Canadian immigration law came into force Friday enabling the government to revoke the citizenship of persons convicted of terrorism, treason, spying or taking up arms against Canadian soldiers.

The latter provision is aimed in part at Canadians who travel to Syria and Iraq to join the Islamic State group fighting a U.S.-led coalition that includes Canada.

A Syrian Christian fighter has beheaded an Islamic State group (IS) militant to avenge people "executed" by the jihadists in northeastern Syria, a monitor said on Friday.

The Syrian Observatory for Human Rights said the incident took place on Thursday in Hasakeh province, where IS holds large areas of the countryside.

World governments are not doing enough to stop their citizens joining jihadists in Syria and Iraq, the U.S. ambassador said ahead of a U.N. Security Council meeting Friday to discuss the threat.

The 15-member council is meeting with interior ministers for the first time after a U.N. study showed a rise in the number of foreign terrorist fighters (FTFs) worldwide.

Images and video footage allegedly showing trucks belonging to Turkey's state intelligence service carrying weapons to rebels in Syria were published Friday in a Turkish daily.

The Turkish government has vehemently denied claims that it is arming rebels fighting in Syria and accused dozens of prosecutors, soldiers and security officers involved in searching the trucks of attempting to bring it down by suggesting it is doing so.