War-torn Syria on Sunday advised its citizens to avoid travel to neighboring Turkey, where massive protests have rocked several cities, because of "a deterioration in the security situation."

The warning issued by the foreign ministry comes as a civil war that has killed tens of thousands ravages Syria, pitting rebels backed by Turkey and other countries against the regime of President Bashar Assad.

Iranian presidential hopeful Ali Akbar Velayati vowed Sunday to introduce "free health care" to tackle a crisis sparked by a lack of medicine and soaring treatment costs, partly due to international sanctions.

Velayati, a 67-year-old U.S.-educated physician, said he would make free health treatment available if elected on June 14, in a speech at Shahid Beheshti University in Tehran.

Yemen's army foiled an attempt by an al-Qaida-linked suicide bomber on Sunday to blow up a strategic pipeline that takes gas from central fields to southern maritime terminals, an official said.

Soldiers opened fire on a vehicle that was speeding towards a gas pumping station, 80 kilometers (50 miles) northwest of Belhaf export terminal on the Gulf of Aden, killing the driver, said the army official.

Businesses in Jordan's restive southern city of Maan closed on Sunday in an act of "civil disobedience" after overnight clashes with police over the murders of two residents, an MP and witness said.

"Civil disobedience in Maan is growing after the authorities failed to arrest the killers of two people," Maan MP Amjad al-Khattab told Agence France Presse, saying the killings took place five days ago.

Syria will allow the Red Cross to enter Qusayr to aid trapped civilians only after the end of a regime assault on the embattled town, its foreign minister told the U.N. chief Sunday.

"Syrian authorities will allow the Red Cross in cooperation with the Syrian Red Crescent access to the area immediately after the end of military operations," Walid Muallem told Ban Ki-moon, state news agency SANA reported.

Gunmen on Sunday killed six people and kidnapped five others in separate attacks in Iraq's western province of Anbar, officials said.

Among those killed were three Syrian truck drivers, while three police were among those kidnapped.

Pope Francis on Sunday appealed to "the humanity" of kidnappers in Syria and urged them to free their hostages, expressing deep concern for the kidnap victims of the two-year-old conflict.

"I appeal to the humanity of the kidnappers and for them to release their victims," the pope told a large crowd as he delivered the Angelus prayer on St. Peter's Square.

Israeli Prime Minister Benjamin Netanyahu on Sunday condemned acts of racism against the country's Arab population after an outcry over an amusement park which segregated Jewish and Arab children.

And he also pledged to bring to justice Israeli extremists behind the wave of so-called "price tag" hate crimes against Palestinians.

Security forces arrested several supporters of moderate presidential candidate Hassan Rowhani in Iran's June 14 election after pictures of detained opposition leader Mir Hossein Mousavi were displayed at a meeting, websites reported Sunday.

Opposition website Kaleme.com reported seven arrests of participants in a ceremony in the Jamaran mosque in northern Tehran on Saturday, with relatives saying "they were taken to Tehran's Evin prison.”

Al-Qaida's military chief in Yemen warned Americans in an audio message posted online Sunday that the Boston bombings revealed a fragile security as he urged Muslims to defend their religion.

Qassim al-Rimi, the military chief of al-Qaida in the Arabian Peninsula, said making bombs such as the ones used in the twin blasts in Boston in April, is within "everyone's reach.”