Updated

The "extremely dangerous" conflict in Syria could have global repercussions, U.N. Secretary-General Ban Ki-moon said Wednesday as fresh violence erupted and an Al Qaeda-inspired group claimed responsibility for two recent suicide bombings in the capital.

The uprising that began a year ago has transformed into an armed insurgency that is pushing the country toward civil war. Because of Syria's close alliances with Iran and the Lebanese militant group Hezbollah, there are deep concerns that the violence could spread beyond its borders, especially if other nations arm the rebels or send in their own troops.

"We do not know how events will unfold," Ban said during a speech in the Indonesian capital, Jakarta. "But we do know that we all have a responsibility to work for a resolution of this profound and extremely dangerous crisis ... that has potentially massive repercussions for the region and the world."

The rebel Free Syrian Army, which includes thousands of army defectors, is the most potent armed group challenging the regime, but it is outgunned and disorganized.

Still, few countries are openly considering arming the opposition, fearing that it would make the conflict worse. The U.N. estimates that more than 8,000 people have been killed since the uprising began.

A string of large-scale bombings near government security buildings in the capital, Damascus, and the northern city of Aleppo have added a new element to the anti-government revolt.

U.S. officials have suggested Al Qaeda militants may be joining the fray and exploiting the chaos.

In a statement posted Wednesday on a militant website, an Islamist group called the Al-Nusra Front to Protect the Levant claimed responsibility for twin suicide bombings in Damascus on Saturday. The blasts, which targeted the air force intelligence building and the criminal security department, killed at least 27 people, the state-run news agency said.

The Associated Press could not verify the authenticity of Wednesday's statement, which said the attacks were in retaliation for the Syrian regime's shelling of residential areas in opposition strongholds in Homs, Idlib, Hama and Daraa.

"We tell the (Syrian) regime to stop the massacres against the Sunnis, otherwise, you will bear the sin of the Alawites," the Al-Nusra Front said. "What is coming is more bitter and painful, with God's will."

The group also has claimed responsibility for earlier suicide attacks.

Al Qaeda's involvement could further fuel the sectarian tensions that the uprising already has stoked.

Al Qaeda's supporters are largely Sunni Muslim extremists. Syria's military and political leadership is stacked heavily with members of the minority Alawite sect, an offshoot of Shiite Islam to which Assad and the ruling elite belong. The Alawite leaders of Syria are closely allied with Shiite Iran.

Sunnis make up the majority of Syria's 22 million people, as well as the backbone of the opposition.

The Syrian uprising began with mostly peaceful protests against the government, inspired by the Arab Spring uprisings across the region. But the regime cracked down violently, opening fire on demonstrations and rounding up thousands of protesters. Assad has justified the crackdown by saying terrorists and foreign extremists are driving the revolt.