Shiite militiamen in Yemen killed two protesters on Thursday when they opened fire on a rally in support of the beleaguered Western-backed president, a medic and an activist said.

Thousands of people had joined the demonstration in the central city of Baida, which the Huthi militiamen who control the capital seized last month, said organizing committee member Fahd al-Tawil.

More than 20 human rights groups issued a joint plea Thursday for the international community to take responsibility for suffering civilians as Syria's civil war approaches its fifth year.

In a report entitled "Failing Syria", they criticized world powers for not implementing a series of U.N. Security Council resolutions on the conflict.

Despite Western and Arab hopes he would be consigned to the dustbin of history, Syrian President Bashar Assad enters his fifth year of war with an increasingly tight hold on power.

Alarm over the sweeping expansion of the Islamic State (IS) jihadist group in Syria and Iraq means that international priorities have shifted away from Assad's removal.

Israelis vote next week in an election seen as a referendum on the tenure of Prime Minister Benjamin Netanyahu, who could lose but still secure a new term in power.

Netanyahu, 65, called for the March 17 vote late last year as his coalition government teetered on the brink of collapse. It will be Israel's third election since 2009 and the premier's biggest challenge after six years at the helm.

Much of Syria is regularly plunged into debilitating darkness, experts said Wednesday, highlighting the scale of the war's devastation as the conflict enters its fifth year.

Analyzing satellite images, scientists from Wuhan University in China found that since March 2011, when the war broke out, "the number of lights visible over Syria at night has fallen by 83 percent," a coalition of 130 non-governmental organizations said in a statement.

The presence of Iranian advisers in the Iraq battle for Tikrit is "concerning" to the United States, Secretary of Defense Ashton Carter said Wednesday.

A mostly Shiite Iraqi force, including Iranian-backed militias, entered Tikrit Wednesday from the Islamic State group after a 10-day push to enter the city.

Attacks in and around Baghdad, mostly bomb blasts, killed at least 17 people on Wednesday, Iraqi police and medical sources said.

The deadliest single attack was a car bombing in the Hurriya district which killed nine people and wounded 30, a police colonel and a hospital official said.

The bodies of four migrants bidding to reach Spain's Canary Islands were recovered off southern Morocco's Atlantic coast Wednesday, a day after 19 others were rescued from a rubber boat, officials said.

The four drowned migrants were found near Tan-Tan, across from the islands, said the officials, quoted by Morocco's MAP news agency.

An Egyptian court jailed four men Wednesday over the brutal street killing of a dog, which was filmed and sparked outrage when the video went viral on the Internet.

The verdict and three-year sentence come as a rare victory for animal rights campaigners, who say authorities often ignore such abuses.

A Bahraini high school student and two teachers have been charged with "insulting Islam" after the boy sang verses from the Koran accompanied by musical instruments, the official BNA news agency reported Wednesday.

Islam allows intonation of Koranic verses, and recordings of chanting are frequently heard in marketplaces or on the radio and television, but singing them to musical accompaniment is prohibited.