BEIRUT - Syrian President Bashar al-Assad faced growing Western anger Tuesday for preventing aid from entering a devastated district of Homs and over accusations of human rights abuses, including pictures said to show torture victims at a hospital in the city.

Dozens of men, women and children returned on foot to Baba Amr, passing bullet-pocked and damaged buildings, days after rebel fighters pulled out after a sustained and heavy military assault. The Red Cross was awaiting approval to distribute aid to the devastated district which endured a month of siege.

Residents who fled the district spoke of bodies decomposing under rubble, sewage mixing with litter in the streets, and a campaign of arrests and executions.

“The smell of death was everywhere. We could smell the bodies buried under the rubble all the time,” said Ahmad, who escaped to Lebanon. “We saw so much death that at the end the sight of a dismembered body ... stopped moving us.”

Despite their chorus of outrage as Homs residents gave more detailed accounts of the siege of Baba Amr, Western leaders have ruled out a Libya-style military intervention in Syria, fearing it could trigger wider conflict in the Middle East.

Calls for action to protect civilians have grown louder as the Alawite-led security apparatus cracked down on protests and an uprising that has its roots in the majority Sunni community and which has raised the prospect of civil war in Syria.

US Senator John McCain, an early advocate of the NATO no-fly zone in Libya which helped to topple Muammar Gaddafi, said the United States should lead an international effort to protect Syrian population centers through air strikes on Assad forces. “The ultimate goal of air strikes should be to establish and defend safe havens in Syria, especially in the north, in which opposition forces can organize and plan their political and military activities against Assad,” said McCain, an influential Republican and former presidential candidate.

In Homs, activists said security forces were carrying out raids in a district next to Baba Amr Tuesday, and reported gunfire and explosions in another area.

In Herak, in Deraa province where the revolt erupted nearly a year ago, residents said armored vehicles and tanks had massed on the western fringe of the city and in parts of the center. There were raids reported in the city of Deir al-Zor.

A Chinese diplomat arrives in Damascus later Tuesday to meet Syria’s foreign minister and to outline Beijing’s plan for halting the violence, while UN envoys Kofi Annan and Valerie Amos are expected in the Syrian capital this week.

The United Nations says more than 7,500 civilians have died in Syria’s crackdown on protests against Assad’s government, which portrays the nearly year-long uprising as a campaign by foreign-backed Islamist insurgents. Authorities said in December 2,000 police and soldiers had been killed since protests, inspired by Arab uprisings which have overthrown four veteran leaders, erupted last March.

Secretly shot video footage aired Monday by a British television station showed what it said were Syrian patients tortured by medical staff at a state-run hospital in Homs.

The video, which Channel 4 said it could not independently verify, showed wounded, blindfolded men chained to beds. A rubber whip and electrical cable lay on a table in one ward. Patients showed what looked like signs of severe beatings.

Channel 4 said the footage was filmed covertly by an employee at the Homs military hospital and smuggled out by a French photo-journalist identified only as “Mani.”

“I have seen detainees being tortured by electrocution, whipping, beating with batons, and by breaking their legs. They twist the feet until the leg breaks,” the employee who made the video told Mani. “They operate without anesthetics ... I saw them slamming detainees’ heads against walls.”

It was not immediately clear whether UN humanitarian affairs chief Amos would have the unhindered access she has been demanding. Several Western diplomats told Reuters privately they were concerned Damascus appeared to have waited until it had “finished the job” of punishing Homs before allowing Amos in.

Residents of Baba Amr said they knew the end was near when the army blew up a 3-km (2-mile) tunnel they had used to smuggle in essentials keeping them alive.

Syrian state television showed pictures of rocket-propelled grenades and guns laid out on the street, weapons the presenter said belonged to “armed terrorists.” Small remote-controlled planes and helicopters were also shown.

“This is the tunnel used by the terrorists to get weapons in and out,” the presenter said, standing in a school building next to a 2-metre (10-foot) hole in the ground.

A man who fled Baba Amr a day after the army went in said soldiers raided houses, arresting men and executed some of them. Activists say at least 60 men were executed since Friday.

“They are cleansing the neighborhood, they are robbing houses, arresting people then executing some. Baba Amr is besieged from all sides. It is a disaster,” said Omar, speaking by telephone from inside Homs after he fled Baba Amr.

“They said they have a list of 1,500 men and they want them all ... They are shooting everything that is moving, even animals. There are bodies in the streets, some are swollen and carry signs of torture,” he said with a trembling voice.

“We were surprised to see how long it lasted. We were not ready for all of that. We thought: ‘Now Baba Amr will break the back of the regime,’ and we thought: ‘OK, let them come,’” said another resident called Omar who fled to Lebanon last week.

Syria has so far brushed off international pressure to halt its violent response to the uprising, bolstered by the resistance of Russia and China to any UN resolutions which they fear could be used to justify foreign intervention.

A Chinese envoy, former ambassador to Damascus Li Huaxin, was expected to arrive in Syria later Tuesday and meet Foreign Minister Walid al-Moualem Wednesday.

China said he would promote a plan which Beijing issued at the weekend as the basis for a solution to the violence.

The UN-Arab League special envoy to Syria, Kofi Annan, will also travel to Damascus Saturday for what would be his first visit since he was named to the post last month.

The appointment of Annan, who has called for all parties to cooperate to help to end the violence in Syria, offers a chance to “rescue fading prospects” for a negotiated solution to the crisis, the International Crisis Group said.

But the Brussels-based conflict resolution group said Annan would have to convince Russia to throw its political and diplomatic weight behind a plan to transfer powers from Assad, ensure an overhaul of Syrian security forces and set in place a process of “transitional justice and national reconciliation.”

It warned that the likely alternative to a political solution involved international steps to arm Syrian rebels, which “could plunge the nation ever deeper into a bloody civil war without prospects for a resolution in the foreseeable future and almost certainly trigger counter-steps by regime allies, thus intensifying the budding proxy war” in Syria.