Renewed fighting unravels Syrian truce

Syrian forces retaliate following a blast at a police station Mortars are fired at stronghold neighborhoods in Deir Ezzor, the opposition says At least three soldiers are killed and 30 people are wounded in fighting, the LCC says (CNN) -- An early morning explosion targeting Syrian police rocked the flashpoint city of Deir Ezzor on Saturday, an attack that further eroded an already shaky temporary cease-fire called over the observance of a four-day Muslim holiday. Thick, black smoke rose from near a military police building in the heart of the city, which was followed by reports of fierce fighting between rebels and government forces, according to opposition groups. The latest violence follows opposition claims of more than 100 people killed in bomb blasts and clashes just hours after the truce began on Friday, coinciding with the start of the Eid al-Adha holiday. Both sides in the civil war accused the other of violating the conditions of the cease-fire, with the government saying its soldiers were responding to "terrorist attacks" -- a term routinely used by President Bashar al-Assad to describe rebel assaults. U.N.-Arab League envoy Lakhdar Brahimi negotiated the truce with the hope of stemming the killings that have gripped the country since March 2011 when protesters inspired by the success of popular revolutions in Egypt and Tunisia took to the streets to demand the ouster of al-Assad. More than 32,000 people, according to the opposition, have been killed in the fighting that followed a brutal crackdown on demonstrators. CNN can't confirm reports of casualties or violence as access to the country by international journalists has been severely restricted. With the attack in Deir Ezzor, one of the centers of heavy fighting in recent months, hopes dimmed that the cease-fire would still take hold for the remainder of the religious holiday. Syrian forces retaliated for the bombing at the police building with a volley of mortar rounds fired at Sunni-dominated neighborhoods, Hani al-Thafiri, an opposition activist working in the city, told CNN. There was no immediate claim of responsibility for the bombing. The Syrian Observatory for Human Rights also reported the explosion and subsequent clashes, though said there were no immediate reports of casualties. The civil war has been playing out largely along sectarian lines, with predominantly Sunni rebels trying to unseat al-Assad and his Alawite minority. Al-Assad is himself an Alawite, which has distant ties to the Shiite faith. The sectarian split in fighting has also spilled over into a diplomatic fracas, with al-Assad backed by Shiite-dominated Iran and the rebels receiving support from Sunni-led Saudi Arabia and other Gulf states. World leaders have condemned the civil war and repeatedly called on al-Assad to step down. Efforts by the U.N. Security Council to stop the violence have been at a standstill, with Russia and China refusing to go along with the United States, France and others call for intervention. Russia, a Cold War ally of Syria, has said Syrians should decide the outcome of the uprising not the United Nations. CNN's Chelsea J. Carter contributed to this report.