Despite fresh political maneuvering on both sides of the Syrian crisis, relentless killing raged on Monday as a peaceful resolution appeared to be a mere fantasy.

At least 21 people were slaughtered across the country on Monday morning, opposition activists said. Intense shelling rained on Deir Ezzor province, where eight corpses were found after regime forces raided the city at dawn, the opposition Local Coordination Committees of Syria said.

Across the country, powerful explosions and heavy gunfire tormented the southwestern city of Douma as forces conducted a raid-and-arrest spree, the LCC said.

"Civilians are being used as human shields to complete the raid campaign" in Douma, the opposition network said.

Over the weekend, the opposition Syrian National Council elected minority Kurdish activist Abdul Basit Sieda to unite dissidents aimed at ousting Syrian President Bashar al-Assad.

Sieda, a native of Hasaka, Syria, but now living in Sweden, called on officials in Syria, Russia, and China "to think carefully about the situation now because the whole stability of the region -- if not the whole stability of the world -- is at stake here. We would like to call upon them to support the Syrian people."

Russia and China have blocked U.N. Security Council resolutions that many other nations said could have pushed al-Assad to stop the killing. The two countries, which have major trade ties with Syria, said they want more balanced resolutions that call for a cessation of violence on all sides.

Sieda also called on Iran "to admit the situation on the ground and respect the will of Syrians" and to prepare "for new relations with the Syrian people based on the full interest of the Syrian and Iranian people."

A recent draft U.N. report accused Iran of exporting arms to Syria in violation of a ban on weapons sales, a Western diplomat told CNN last month. Some analysts say Iran has continued to arm Syria in its brutal crackdown on the opposition.

Sieda vowed his country will be "a free democratic state."

Dozens of countries have recognized the SNC as a legitimate representative of the Syrian opposition, though many members of the group's leadership are expatriates.

When asked how he planned to bridge a gap between the Syrian opposition in exile and the opposition inside the country, Sieda said, "We are in direct communication and contact with revolutionary forces inside. We are always communicating with them. ... The relationship between us and the forces inside has never been stronger."

But al-Assad has said he will not deal with opposition members influenced from the outside.

While Sieda railed against the violence committed by al-Assad's forces, the regime itself announced a new stage in its argument that "armed terrorist groups" are actually responsible for the violence in the country.

A "documentary" shown on Syrian state-run TV revealed "that terrorists of various nationalities from the terrorist organization Jabhet al-Nasra, which is affiliated with al Qaeda, planned and carried out" bombings in Damascus on March 8. The cars used in the attack were driven by a Jordanian terrorist and a Syrian Palestinian, "and were trailed by an Iraqi," state-run news agency SANA reported.

Jabhet al-Nasra is also known as the al Nusra Front.

SANA also said 22 "army, law enforcement and civilian martyrs" were buried Sunday.

The LCC, meanwhile, said 53 people were killed Sunday, including 26 in Homs.

Among the dead Sunday was citizen journalist Khaled Bakr, founder of the Baba Amr media center, the LCC said. Baba Amr, a besieged neighborhood of Homs, came under weeks of incessant shelling by the Syrian regime earlier this year, opposition activists have said.

At a mosque in Maarat al-Numan, part of Idlib province, El Mundo correspondent Javier Espinosa said he saw six bodies destroyed beyond recognition. "They were in pieces," he told CNN.

Residents said people were leaving a mosque when a rocket hit in the middle of the street, hitting no one. As residents gathered after to assess the impact, a second rocket hit.

The rocket had Russian markings on the shell, Espinosa said.

Russia is viewed as a key ally of Syria. While Western countries have criticized Russia for its arms trade with Syria, Russia has insisted it is not propping up al-Assad's regime.

Russian Foreign Minister Sergey Lavrov said Saturday there was no alternative to U.N.-Arab League special envoy Kofi Annan's peace plan, despite mounting evidence that it's being violated daily.

"The situation looks more and more grim," Lavrov said. "For the first time since the beginning of this crisis, we see the question of foreign intervention. And our position remains unchanged. We will never agree to sanction the use of force in the U.N. Security Council."

The United Nations has said at least 9,000 people have died since the Syrian crisis erupted in March 2011. Opposition groups, however, say the toll is much higher, with estimates ranging from at least 12,000 to more than 14,000.

CNN cannot independently confirm reports of casualties or violence in Syria, as the government has restricted access by international journalists.