Egyptians voted on Saturday in the final round of a referendum on a new constitution championed by President Mohamed Morsi and his Islamist allies, but with little prospect of the result quelling fierce protests.

On the eve of polling, clashes in Egypt's second city Alexandria injured 62 people as stone-throwing mobs torched vehicles, underlining the turmoil gripping the Arab world's most populous nation.

The Libyan army is deploying units to help bolster security in the eastern city of Benghazi, a military spokesman said on Friday, a day after clashes there killed four people.

"Army units will secure the entrances and exits of the city as well as strategic sites until security is restored," army spokesman Ali al-Sheikhi told AFP, adding that the decision was in coordination with the interior ministry.

Tunisia announced on Friday that it had arrested 16 men suspected of belonging to a group with ties to al-Qaida in the Islamic Maghreb, in the western regions of Kasserine and Jendouba near the Algerian border.

"We have discovered a terrorist group linked to al-Qaida in the Islamic Maghreb in a training camp run by three Algerians close to AQIM leader Abou Moussab Abdel Wadoud," in the Kasserine region, Interior Minister Ali Laarayedh told reporters.

Armed extremists killed a woman in Yemen's main southern city of Aden when they raided several homes whose owners allegedly have alcoholic drinks, residents and a security official said on Friday.

"More than 10" armed men on motorbikes stormed three houses in Aden's Memdara neighborhood on Thursday, residents said.

An attack by Syrian rebels on an electricity pylon on Friday caused a power outage in several areas of Damascus, state television said.

"A group of terrorists destroyed a transmission tower, leading to a power cut," said the broadcaster, using the regime's standard terminology for rebels fighting to unseat President Bashar Assad.

November's eight-day confrontation between Israel and Gaza militants claimed the lives of 177 Palestinians, mostly civilians, and six Israelis, medical sources on both sides said.

A previous toll at the end of November stood at 174 Palestinian fatalities, and three more people have died of their wounds during December, according to emergency services in the Hamas-ruled Gaza Strip.

European Union foreign policy chief Catherine Ashton and Russian Foreign Minister Sergei Lavrov on Friday issued a rare and strong joint condemnation of Israeli plans to massively expand settlements.

A statement released during an EU-Russia summit said the two sides were "deeply dismayed by and strongly oppose Israeli plans to expand settlements in the West Bank and in particular plans to develop the El area."

FBI agents on Friday questioned a Tunisian man suspected of involvement in a deadly September attack on the U.S. consulate in Libya, but in the absence of defense lawyers, his solicitor said.

"The judge prevented any lawyers from attending the questioning" of Ali Hamzi, Abdelbasset Ben Mbarek told AFP, adding that his client was interrogated as a suspect rather than as a witness.

New clashes between pro- and anti-Damascus fighters erupted in a Palestinian camp in south Damascus on Friday, hours after the return of thousands of people who fled earlier violence, a monitoring group said.

"The fresh battles pitted fighters from the pro-regime popular committees against Syrian and Palestinian rebels opposed to President Bashar Assad," said Syrian Observatory for Human Rights director Rami Abdel Rahman.

Gunmen kidnapped three tourists in Yemen's capital on Friday and drove off with them to an unknown location, a security official told AFP, adding that their nationalities were not yet known.

"Four masked gunmen in a vehicle attacked a shop in central Sanaa and abducted three foreign tourists -- a woman and two men," said the official, adding that the tourists were taken away at gunpoint.