The European Union added Tuesday the commander of Syria's special forces, a militia chief and a slew of generals to a new list of Syrians hit by sanctions over a crackdown on protesters.

The military men and a lawyer are among 18 extra people blacklisted by the 27-state EU, bringing to 74 the members of President Bashar al-Assad's regime hit in past months by assets freezes and travel bans.

More than 100 demonstrators stormed the Jordanian embassy in Damascus and tore down the flag in protest at King Abdullah II's call for Syrian President Bashar Assad to go, Jordanian newspapers said Tuesday.

It was the fourth such protest against embassies of regional powers by angry Assad loyalists since the Arab League voted on Saturday to suspend Syria and impose sanctions against the regime over its bloody eight-month crackdown on peaceful protesters.

A wave of violence killed at least 50 people in Syria in one day, many of them Syrian soldiers who came under attack from army defectors, activists said Tuesday.

The unrest in Syria appears to be escalating as President Bashar Assad comes under mounting pressure — not only from the West but from his Arab neighbors, as well.

The exiled Syrian opposition on Tuesday failed to convince Moscow to toughen its stance against the regime of defiant leader Bashar al-Assad, the leader of the Paris-based dissident delegation said.

Members of the largest and most representative Syrian opposition grouping, the Syrian National Council -- led by its head Burhan Ghalioun -- traveled to Moscow for talks with Russian Foreign Minister Sergei Lavrov.

The head of the Organization of the Islamic Cooperation on Monday warned of a possible internationalization of the Syrian crisis if the regime does not comply with calls for reform and end the bloodshed.

If Syria "does not comply with the legitimate demands of the Syrian people and international calls by the OIC, the Arab League and the United Nations, it will risk the internationalization of its crisis," Ekmeleddin Ihsanoglu said.

The Arab League is preparing to send observers to Syria but needs guarantees from Damascus on their mission and the rights of each side, the organization’s chief Nabil al-Arabi said Monday.

The decision to send a 500-strong delegation follows a vote to suspend Damascus from the 22-member Arab bloc over its deadly crackdown on protests. It came a day after Syria said it would welcome such a mission.

European Union nations tightened the noose on Syria on Monday, slapping new sanctions on President Bashar al-Assad's regime and urging U.N. action to protect civilians after eight months of bloodshed.

Foreign ministers from the 27-nation bloc blacklisted a further 18 Syrians, mostly members of the military, bringing to 74 the members of Assad's inner circle hit in past months by an EU assets freeze and travel ban.

Jordan's King Abdullah II on Monday became the first Arab leader to call for Syrian President Bashar al-Assad to step down, in a BBC interview.

"I believe, if I were in his shoes, I would step down," the king said. "I would step down and make sure whoever comes behind me has the ability to change the status quo that we're seeing."

Iraqi Foreign Minister Hoshyar Zebari on Monday defended his country's abstention from a vote on suspending Syria from the Arab League, emphasizing that events in Syria have a direct impact on Iraq.

The Arab League voted on Saturday to suspend Syria, which has been trying to crush a popular uprising against President Bashar Assad's regime since March.

Turkey's foreign minister warned embattled leaders in Syria and other Middle East countries on Monday that those who cannot meet their people's demands "will go".

Ahmet Davutoglu spoke a day after Ankara expressed outrage after attacks on its diplomatic missions in Syria by pro-regime protesters and summoned the country's envoy.