BEIRUT: In diametrically conflicting attitudes reflecting the political schism between Lebanon’s rival factions, Hezbollah and former Prime Minister Saad Hariri differed sharply Friday over who was responsible for the twin suicide car bombings that targeted security service buildings in the Syrian capital Damascus, killing at least 44 people.

While Hezbollah accused the United States of responsibility for the bombings, calling it the “mother of terrorism,” Hariri said the blasts were the work of the regime of Syria’s embattled President Bashar Assad.

Syrian officials say at least 44 people were killed and more than 100 wounded in Friday’s bombings in Damascus, which they have blamed on Al-Qaeda. The attacks were the first of their kind against the powerful security services in the heart of the capital since unprecedented protests against Assad’s regime erupted in mid-March.

The blasts came a day after an advance team of Arab League observers arrived in Damascus to monitor Syria’s promise to end its violent crackdown on protesters.“These bombings which resulted in the death and injury of dozens of people, mostly women and children, are the specialty of the United States, the mother of terrorism,” Hezbollah said in a statement. It accused the U.S. of “specializing in targeting, killing and terrorizing the innocent in order to push them into bowing to the U.S. policy that is seeking to achieve the Zionist interest which the Americans put above any other consideration.”

Hezbollah, which is a major ally of Assad, said the timing of the bombings clearly signaled they were an act of revenge for the U.S. “defeat” in Iraq following the withdrawal of its troops from the warn-torn country.

“This horrific terrorist crime committed by the enemies of humanity in the city of Damascus came one day after the coordinated bombings that targeted Baghdad and other Iraqi cities,” the statement said. “This signals that the parties that stand to lose from the big defeat inflicted on the United States, which led to the humiliating withdrawal of its troops from Iraq, have begun a cowardly, bloody act of revenge by targeting all forces and states that helped the heroic Iraqi resistance in its Jihad [holy war] to evict the U.S. occupation.”

A cold war has been heating up for months between Washington and Hezbollah, with the militant group denouncing the planting of CIA “spies” in its ranks and the U.S. accusing the group of illegal financial and drug dealings in recent weeks.

Commenting on Hezbollah’s accusation that the U.S. was behind the Damascus bombings, Hariri, speaking to his supporters on the popular social networking website Twitter, said: “We are at a loss. Is it the specialty of Al-Qaeda or the specialty of America? Something that is really puzzling. I think that the bombings were the work of the Syrian regime.”

Asked whether the attacks in Damascus were designed to target Arab observers sent by the Arab League to monitor a League plan to end a nine-month brutal crackdown on protesters, Hariri said: “This is one of the biggest possibilities.”

Asked whether Assad, who is facing the most serious threat to his 11-year rule from the popular uprising, was stronger than NATO states, Hariri said: “A weak is the one who kills. This is his end.” Hariri and his March 14 allies have come out staunchly in support of Syrian protesters demanding Assad’s ouster.

Meanwhile, President Michel Sleiman telephoned Assad to condemn the bombings, saying they were aimed at scuttling Arab efforts to end the crisis in Syria. “The attack, which coincided with the arrival of the advance observer team in Syria, is aimed at disrupting the Arab solution that was agreed upon between Syria and the Arab League,” Sleiman said, according to a statement released by his office.

Speaker Nabih Berri sent a cable to Assad condemning the “terrorist bombings” in Damascus and extending his condolences for the victims who fell, the state-run National News Agency said.

Former Prime Minister Fouad Siniora, head of Hariri’s parliamentary Future bloc, strongly condemned both the Damascus bombings and the Syrian authorities’ continued crackdown on protesters.

“The innocent lives that were killed and the blood that was shed are Arab lives and the blood shed is Arab blood. Hence, we strongly condemn these bombings,” Siniora said, adding: “We also at the same time condemn the continued fall of scores of martyrs throughout Syria, particularly what happened today and yesterday as a result of a blind crackdown used by Syrian authorities against innocent civilians who are peacefully demanding freedom and dignity.”

“This bloody path used in dealing with matters can only harm Syria and all the Arabs,” he added, and urged Syrian authorities to comply with the the Arab initiative and ensure freedom for the Arab observers to do their job.