Blast rocks central Damascus
(CNN) -- Reports of carnage and widespread violence in Syria continue to grow despite the U.N. Security Council's agreement to boost the number of monitors in the country.
A huge explosion rocked central Damascus on Tuesday, according to the opposition Syrian Observatory for Human Rights. The group had no immediate information on possible casualties.
Syria said a bomb was attached to a car and injured the driver. On state-run news agency SANA, the country blamed an "armed terrorist group." The attack took place in the neighborhood of Merja, SANA said.
Throughout the Syrian uprising, authorities have blamed violence on "armed terrorist groups."
On the opposition side, at least 11 people were killed in Syria Tuesday, including two who died as a result of torture, according to the opposition Local Coordination Committees of Syria. Two of the dead are women, the LCC said.
Six of the deaths were in the beleaguered city of Homs; three were in Damascus, and two were in Damascus suburbs, the group said.
Regime forces pummeled Homs and Hama with heavy shelling, the LCC said, just days after U.N. observers left those cities. At least 50 of the 80 deaths across Syria on Monday took place in Hama, the group said.
Farther south, tank artillery and mortar rounds rained Tuesday on the city of Douma, said an opposition activist identified as Fateh for safety reasons.
In Idlib, security authorities moved 20 corpses from a hospital to an undisclosed location coinciding with news of observers arriving in the area, the LCC said.
In the Damascus suburb of Douma, a huge explosion was reported, the LCC said. In another suburb, Karafbatna, several activists were reported to have been arrested, apparently at random, at a checkpoint in the center of the city, the LCC said.
Meanwhile, in Damascus, a government intelligence officer was assassinated Tuesday morning, said the Syrian Observatory for Human Rights.
Syria, meanwhile, said armed terrorists assassinated a retired officer and his brother in the province of Damascus Monday night, in the neighborhood of Fadel.
A SANA report also said the "bodies of seven army and law-enforcement martyrs" were buried Tuesday.
U.N.-Arab League special envoy Kofi Annan is expected to brief the Security Council on Tuesday as the peace plan he brokered appeared so far unable to quash the bloodshed that has plagued Syria for more than a year.
Only a handful of U.N. observers are in the country, but the Security Council recently authorized sending up to 300 monitors for 90 days.
"It is our hope that the deployment of observers will help to stop the killing and consolidate the calm," said B. Lynn Pascoe, U.N. under-secretary-general for political affairs. "The objective, however, is clearly not to freeze the situation but to create the conditions for a serious and credible political process."
The monitors are tasked with observing a cease-fire imposed on April 12, part of a six-point peace plan laid out by Annan and accepted by the Syrian government.
But the cessation of armed violence in Syria remains "incomplete," and human rights violations are still perpetrated with impunity, Pascoe told the Security Council on Monday.
International leaders, including U.S. President Barack Obama, are ratcheting up pressure on the Syrian regime.
"I have signed an executive order that authorizes new sanctions against the Syrian government and Iran and those who abet them for using technologies to monitor and track target citizens for violence," Obama said Monday. "... It's one more step that we can take toward the day that we know will come -- the end of the Assad regime."
In addition, European Union foreign ministers agreed to ban the export of goods and technology that might be used by Damascus to produce chemical or biological weapons.
The EU also agreed to ban export of luxury goods to Syria, according to a statement Monday by British Foreign Secretary William Hague.
"Despite the urgent need for Assad to end the violence immediately, he and his close supporters continue to lead comfortable lives," Hague said.
Though they agreed to beef up the observer mission, Russia and China, two permanent countries on the 15-member Security Council, have vetoed attempts to take tougher action against the Syrian regime.
Russian U.N. Ambassador Vitaly Churkin defended his country's position.
"As a matter of principle, we believe that the U.N. Security Council is not about regime change," Churkin told CNN's Christiane Amanpour on Monday. "We believe that ... if there is crisis in a country, the role of the international community should be to help the parties involved to find a political, peaceful way out of this crisis.
"And when we saw some of the resolutions -- which included sanctions -- we knew that those were resolutions which were heading in the direction of regime change by force, which would, in turn, lead only to much more bloodshed in Syria."
The Annan peace plan calls for the government and the opposition to end the violence, provide access for humanitarian groups, release detainees and start a political dialogue.
Susan Rice, U.S. ambassador to the United Nations, expressed doubt that al-Assad's regime would follow through with Annan's plan.
"The regime's long track record is one of dependable deceit and deception," she said. "We will work to ensure there will be consequences should the Syrian regime continue to ignore this council's decisions, press ahead with its murderous rampage and flout the will of the international community."
On Saturday, Syrian U.N. Ambassador Bashar Jaafari said security forces will exercise the "utmost degree of restraint" but remain prepared to defend their national interests against terrorists.
CNN cannot independently verify reports of violence and deaths within Syria, as the government has restricted access by international media.
Syria has been engulfed in violence since March 2011, when the government started started cracking down on demonstrators who were peacefully protesting the regime of al-Assad. The president's family has ruled Syria for 42 years.
The United Nations estimates at least 9,000 people have died since the protests began, while activist groups put the death toll at more than 11,000. Rice put the total at 10,000.