U.S. expels Syrian envoy Zuheir Jabbour over Houla massacre along with other Western nations

This image made from amateur video released by the Shaam News Network May 28, 2012, purports to show black smoke rising from buildings in Homs, Syria.
AP Photo/Shaam News Network via AP video

Updated at 3:09 p.m. ET

(CBS/AP) WASHINGTON - The United States expelled Tuesday Syria's top envoy in Washington in response to a particularly gruesome massacre in which the United Nations says families, including children, were shot at close range in their homes, CBS Radio News correspondent Cami McCormick reports.

Zuheir Jabbour, Syria's charge d'affaires at the nation's embassy, has 72 hours to leave the country, State Department spokeswoman Victoria Nuland said in a statement. Syria has not had an ambassador in the United States since the previous envoy left last year to take another post.

"We hold the Syrian government responsible for this slaughter of innocent lives," said Nuland. "This massacre is the most unambiguous indictment to date of the Syrian government's flagrant violations of its U.N. Security Council obligations."

No action was taken against the handful of technical staff remaining at the Syrian Embassy, Nuland told reporters at an afternoon press conference.

The decision comes as governments around the world expelled ambassadors and top Syrian diplomats Tuesday in an unusually coordinated blow to Syria's leaders.

Special Section: The Arab Spring
U.N.: "Entire families" shot in homes in Syria
Russia condemns ally Syria over massacre of 108

Cranking up the pressure on increasingly isolated Syrian President Bashar Assad,

Britain, Canada, Australia, France, Germany, Italy, Spain, Bulgaria and the Netherlands also took action Tuesday against Syrian diplomats. Britain's foreign secretary said the countries involved in Tuesday's expulsions would also push for tougher sanctions against Syria.

The moves came after the killings Friday in Houla, a collection of farming villages in Syria's Homs province — one of the deadliest single events in a 15-month-old uprising against Assad that has killed thousands.

A U.N. report Tuesday said 49 children and 34 women were among the 108 people who died, but it did not decisively say who carried out most of the killings.

"We are at a tipping point," special envoy Kofi Annan told reporters Tuesday in Damascus, following a meeting with Assad. "The Syrian people do not want the future to be one of bloodshed and division."

He called on the government and the armed opposition to stop all violence. Later, Nuland, the State Department spokeswoman, said, "From our perspective, this has been tipping in the wrong direction for a long time."

According to the state-run news agency, SANA, Assad blamed terrorists and weapons smugglers for scuttling Annan's peace plan. The regime denies there is any popular will behind the country's uprising, saying foreign extremists and terrorists are driving the unrest.

The new information provided by the U.N. draws attention to the role of the shabiha in 15 months of violence in Syria. Assad's government often deploys pro-regime thugs or armed militias to repress protests or carry out more military-style attacks on opposition areas.

They frequently work closely with soldiers and security forces, but the regime never acknowledges their existence, allowing it to deny responsibility for their actions.

A Syrian official denied again on Tuesday any involvement.

"It is irrational that any party who wants to make Annan's mission a success would ever commit such a massacre," Deputy Foreign Minister Faisal Mekdad told reporters. He said Syria remained committed to Annan's plan and "had not committed a single violation."

Activists have posted videos of tanks and armored vehicles in the middle of cities, a violation of the plan, and U.N. observers said they found spent tank and artillery shells in Houla after the massacre there. Funeral videos also showed local rebels among the mourners — making it unlikely they carried out the killings.

Diplomats at the U.N., the European Union and the Arab League have been working since the Houla massacre to coordinate new action against Syria's government, French Foreign Ministry spokesman Bernard Valero said.

"This is the most effective way we've got of sending a message of revulsion of what has happened in Syria," Australian Foreign Minister Bob Carr said in Canberra in reference to the expulsions. In a statement, he called the Houla killings a "hideous and brutal crime" and said Australia would not engage with the Syrian government unless it abides by the U.N. cease-fire plan.

The expulsions up the pressure on Syrian allies such as Russia. Russian President Vladimir Putin is traveling to Germany and France this week and is likely to come under even greater criticism of his Syria-supportive stance.

"We have to continue our work with the Russians," British Foreign Secretary William Hague said. "We will continue to discuss this with Russia. Russia has particular leverage on the regime and therefore has a particular role in this crisis."

Hague said that the situation in Syria is more complicated than what international powers faced in Libya last year, when the United Nations approved intervention against dictator Muammar Qaddafi's regime.

Britain is expelling three Syrian diplomats to protest the Houla killings, among them Charge d'Affaires Ghassan Dalla — the country's top ranking diplomat in London.

In Canada, Foreign Minister John Baird said all Syrian diplomats and their families have five days to leave. Another Syrian diplomat expected in Canada will be refused entry.

In France, Syria's former colonial ruler, new President Francois Hollande showed that he is not backing down from his predecessor Nicolas Sarkozy's tough line on Syria.

Syrian Ambassador Lamia Shakkour was notified Tuesday that she is persona non grata, along with two other embassy officials, the French Foreign Ministry said. Hollande said Shakkour is being expelled but that the timing is complicated by her dual status as Syria's ambassador to Paris-based UNESCO.