Saudi authorities have arrested 10 more suspects in an alleged Iranian spy ring unveiled two months ago, an interior ministry spokesman said on Tuesday.

The eight Saudis, a Lebanese and a Turk bring the number of people arrested to 28, the official SPA news agency quoted the spokesman as saying.

The U.N.'s children's agency warned Tuesday that up to 20,000 civilians, mainly women and children, could be trapped by harsh fighting in the Syrian town of Qusayr.

"The situation is desperate," UNICEF spokeswoman Marixie Mercado told reporters in Geneva.

The U.N. said Tuesday the number of Syrian refugees flooding into Jordan had suddenly fallen from several thousand a day to close to zero, warning that fighting may be blocking people in need from coming.

"In Jordan in the last four days, we have seen a significant drop in the number of (Syrian) refugees arriving," Panos Moumtzis, who heads the U.N. refugee agency's response to the Syria crisis, told reporters in Geneva.

The Syrian regime has put forward a list of five officials including Prime Minister Wael al-Halqi as potential negotiators in talks with the opposition, European diplomatic sources said on Tuesday.

The list, provided to Moscow in early March, also includes deputy prime minister Qadri Jamil and three other officials, the sources said.

Iran said Tuesday it is willing to attend an upcoming peace conference on Syria, arguing all influential parties must be included in the process for it to be a success.

"The condition for success in Geneva is that all countries with influence on events in Syria participate," foreign ministry spokesman Abbas Araqchi told reporters.

Saudi Arabia on Tuesday executed five Yemenis and displayed their bodies in public for killing a national and forming a gang that committed robberies across several towns in the kingdom, the interior ministry said.

The five were executed in the southwestern town of Jizan, bringing the number of people executed in the kingdom this year to 46, according to an Agence France Presse tally.

Violence in Iraq, including a bombing near a mosque, killed 18 people on Tuesday, officials said, the latest in a spate of unrest that has cost more than 370 lives so far this month.

The bomb near a mosque in Abu Ghraib, west of Baghdad, killed five people and wounded at least 16, officials said.

Syria's army destroyed an Israeli military vehicle which it said had crossed the sensitive ceasefire line in the Golan Heights on Tuesday, the military said in a televised statement.

"Our armed forces have destroyed an Israeli vehicle with everything that it had in it... The vehicle had crossed the ceasefire line and was moving towards the village of Bir Ajam, situated in the liberated Syrian zone" of the Golan, it said.

Algerian Prime Minister Abdelmalek Sellal on Monday broke official silence on the health of President Abdelaziz Bouteflika, saying he is convalescing in Paris after a mini-stroke and was "never in danger".

"I would like to reassure our compatriots on the state of health of the president of the republic... he was never in danger and his health is improving day by day," Sellal said in a statement carried by the APS news agency.

Secretary of State John Kerry was returning to the Middle East Monday, aiming to shore up peace efforts as he seeks to help end the Syria war and coax Israel and the Palestinians back to talks.

The new top U.S. diplomat -- making his fourth visit to Israel in a little over three months -- left Andrews Air Force Base in Maryland, first headed for key Gulf ally Oman, which also maintains close ties to Iran.