Valerie Amos
Valerie AmosReuters

UN humanitarian chief Valerie Amos toured the devastated Syrian neighborhood of Baba Amr in Homs on Wednesday as President Bashar al-Assad vowed to "fight foreign terrorists."

Amos and a Syrian Red Crescent team were allowed in after she secured a commitment from Foreign Minister Walid Muallem that she could go anywhere she wanted in the country.

"She says that the parts of Baba Amr they saw were completely devastated," UN humanitarian affairs spokeswoman Amanda Pitt said. "There were very few people around. They did see a few people looking for their belongings, that kind of thing."

Reports of "mop-up operations" including the rape and murder of residents by Syrian troops circulated in the days between the end of fighting in Baba Amr on March 1st, and and human rights workers being admitted on Wednesday.

Rupert Colville, spokesman for the UN High Commissioner for Human Rights Navi Pillay, described on Wednesday a video that has emerged of torture victims in the Military Hospital in Homs as "truly shocking".

The video, broadcast on Britain's Channel 4, shows wounded civilian victims blindfolded and chained to their hospital beds, some of them with clear torture marks on their bodies.

The month-long crackdown on the rebel-held Homs neighborhood brought international condemnation, and no fewer than 700 civilian deaths, but the criticism has not broken Assad's stride.

A year into his bloody crackdown, Syrian forces continue to round-up and execute suspected army defectors, and to indiscriminately target neighborhoods suspected of being insurgent strongholds with artillery and sniper fire.

Assad blames al-Qaeda and other terror groups for the unrest that has engulfed Syria.

"The Syrian people, who have in the past managed to crush foreign plots... have again proven their ability to defend the nation and to build a new Syria through their determination to pursue reforms while confronting foreign-backed terrorism," al Assad said, according to state news agency SANA.

Meanwhile, viscous clashes broke out in the village of Hirak on Wednesday after a day of shelling by Syrian tanks. The fighting there is said to be some of the worst in Daraa province, which birthed the uprising against Assad.

Fighting also continued in Rastan, where fighters from the Syria Free Army have put up stiff resistance during three days of shelling and sniper fire.

SFA fighters are believed to be some 20,000 in number and are mostly army defectors armed as light infantry. They have mounted numerous deadly ambushes and hit-and-run raids on Assad's forces, but have yet to gain the momentum, numbers, and arms necessary to oust Assad.

Traditional allies of Assad - Moscow, Tehran, and the Hizbullah terror group in Lebanon - appear convinced he can whether the storm as the West refuses to give the rebels military arms or support.

Despite having asked the Pentagon for a review of military options in Syria after intense criticism from Sen. John McCain, US President Barack Obama has made it clear he's not inclined to do more than sanction and condemn.

"For us, to take military action unilaterally, as some have suggested, or to think that somehow there is some simple solution, I think is a mistake," Obama said on Tuesday.

"What happened in Libya was we mobilized the international community, had a UN Security Council mandate, had the full cooperation of the region, Arab states, and we knew that we could execute very effectively in a relatively short period of time. This is a much more complicated situation," Obama said.

Marine General James Mattis, head of US Central Command, told the Senate Armed Services Committee it would take a significant military commitment to create safe havens in Syria where aid could be delivered, let alone directly intervene.

He also said the advanced air defense weapons Russia has provided to Syria would make it difficult to establish a no-fly zone there as part of an effort to help the rebellion.

US secretary of state Hillary Clinton has explicitly ruled out arming the Syrian Free Army.

The United Nations says more than 7,500 people have been killed by Assad's forces since the uprising began.