Panetta: Syria violence 'spinning out of control'

Comments come hours after Syria's defense minister and Assad's brother-in-law were killed in a

The situation in Syria is "spinning out of control," U.S. Defense Secretary Leon Panetta said on Wednesday, adding that President Bashar Assad's government would be held responsible if it failed to safeguard its chemical weapons sites.

Syria's defense minister and Assad's brother-in-law were killed in a Damascus suicide bomb attack carried out by a bodyguard on Wednesday, the most serious blow to the president's high command in the country's 16-month-old rebellion.

"This is a situation that is rapidly spinning out of control," Panetta said, adding that the international community needed to "bring maximum pressure on President Bashar Assad to do what's right, to step down and allow for that peaceful transition."

Panetta's comments to a Pentagon news conference followed closed door talks with his British counterpart, Defense Secretary Philip Hammond. Hammond, speaking alongside Panetta, said he believed the situation in Syria was deteriorating and "becoming more and more unpredictable."

The Damascus attack, Hammond said, showed the country's growing instability as the violence gets closer to the heart of the government.

"I think what we're seeing is an opposition which is emboldened, clearly an opposition which has access increasingly to weaponry, probably some fragmentation around the edges of the regime as well," he told reporters.

The Assad government appears to be quietly shifting some chemical weapons from storage sites, Western and Israeli officials have said, but it is not clear whether the operation is merely a security precaution amid Syria's escalating internal conflict.

The Syrian government denies carrying out the operation. Syrian's undeclared stockpile - believed to be the largest of its kind in the Middle East - reportedly includes sarin nerve agent, mustard gas and cyanide.

"We've made very clear to them that they have a responsibility to safeguard their chemical sites and that we will hold them responsible should anything happen with regards to those sites," Panetta said, adding that the United States was working closely with its allies on the issue.

Hammond said it was important to marshal the support of those countries that still give tacit support to the regime, in what appeared to be a veiled reference to Russia and China.

"So our diplomacy has to focus on getting those who have the greatest influence with the regime to ensure that it acts responsibly in relations to chemical weapons," Hammond said.

Syria's rebel FSA claims deadly attack on top officials

An undated handout photo distributed by Syrian News Agency (SANA) on July 9, 2012 shows Deputy Prime Minister and Defence Minister Dawoud Rajha (C) attending with other officials a Syrian air defence live ammunitions exercise in an undisclosed location.

Syria's rebel Free Syrian Army (FSA) claimed responsibility for a deadly Damascus attack on Wednesday that killed two top regime officials, the defence minister and the president's brother-in-law.

The command of the FSA "announces the good news of the outstanding operation this morning that targeted the National Security headquarters and the killing" of the officials "responsible for barbaric massacres," it said in a statement.

Syria's army said it would "continue fighting terrorism" after a suicide bombing at the National Security headquarters in Damascus killed two top regime officials on Wednesday.

"The terrorist act increases the armed forces' determination to cleanse the country of terrorist groups," the army said in a statement.

Syria's defence minister and President Bashar al-Assad's brother-in-law were both killed in a suicide bombing in Damascus on Wednesday that targeted National Security headquarters, state television said.

Defence minister General Daoud Rajha and deputy defence minister Assef Shawkat -- two of Syria's top security officials -- were killed in the attack, the broadcaster said.

According to Syria TV, Syrian government appointed General Fahad Jassim al-Freij as defence minister.

Security officials told AFP that several other participants attending a high-level meeting were wounded in the blast. A security source said the suicide attacker targeted the gathering with an explosives belt.

The officials said Interior Minister Mohammed al-Shaar was "badly wounded" and that the assistant to the vice-president, Hassan Turkmeni, was also injured.

The morning attack targeted the regime's most senior security chiefs, state television said.

It happened in the high security Rawda district in the heart of the capital as battles between regime forces and the Free Syrian Army (FSA) raged in Damascus for the fourth consecutive day.

Rajha, a Christian, was defence minister, deputy army chief and deputy head of the Council of Ministers. Assad himself is overall commander of the military.

Shawkat was deputy defence minister and a former military intelligence chief.

The National Security branch -- a linchpin of Syria's security apparatus -- is headed by General Hisham Ikhtiyar, who was also wounded in Wednesday's blast.

In mid-May this year, a reported attempt was made to poison Rajha, Ikhtiyar, Shawkat, Turkmeni and other key regime figures. A delivery boy was said to have added mercury to their food during a meal before fleeing.