BEIRUT - A major Syrian pipeline carrying oil to a refinery in restive Homs province was blown up Thursday in an attack the state-run news agency blamed on "saboteurs" as activists reported fresh violence from the government crackdown on a popular uprising.

The blast caused no casualties but sent a plume of black smoke into the sky. A government official said the blast caused a fire that burned for hours. The official spoke on condition of anonymity because he was not authorized to speak to the media.

"An armed terrorist group on Thursday committed an act of sabotage," the state-run SANA news agency said.

It was not clear who was behind the pipeline explosion at a time when violence in Syria is spiraling out control, unearthing long-standing grievances and resentments. The opposition accuses the government of playing on fears of religious extremism and terrorism to rally support behind Assad, who has portrayed himself as the only force that can stabilize the country.

There were two similar blasts on Syrian pipelines in July and it is still not know who was behind them.

Nomair Makhlouf, the general director of the Syrian Oil Company, said the pipeline serves Syria's domestic requirements and carries 140,000 barrels a day.

Also Thursday, activists said security forces killed up to 14 people, most of them in Homs. The reports could not be independently confirmed as Syria has banned most foreign journalists from the country and prevented independent reporting.

Syria is trying to crush a 9-month-old popular uprising, but the conflict is turning more violent as once-peaceful protesters increasingly take up arms.

On Wednesday, President Bashar Assad claimed in a rare interview he never ordered the brutal suppression of the uprising and insisted only a "crazy person" would kill his own people. Apparently trying to distance himself from violence that the U.N. says has killed 4,000 people since March, Assad laughed off a question about whether he feels any guilt.

"I did my best to protect the people," he told ABC's Barbara Walters during an interview at the presidential palace in the Syrian capital, Damascus. "You feel sorry for the life that has been lost, but you don't feel guilty when you don't kill people."

"No government in the world (kills) its people unless it is led by a crazy person," Assad added.

Assad is under growing international pressure, in part from sanctions imposed by Turkey, the Arab League and the European Union aimed at squeezing the ailing economy and forcing the regime to halt the bloodshed.

The EU has banned oil imports from Syria in a move that costs the embattled regime millions of dollars each day. But the sanctions are also hurting Syria's trading partners in the region.

Jordan asked the Arab League to exempt it from the bloc's sanctions on Syria over concerns of the toll they will take on the kingdom's already frail economy, a senior government official said.

"Jordan supports the Arab consensus regarding the sanctions on Syria, but we have to cater to our economic interests," the official said, insisting on anonymity because of the sensitivity of the matter.

Syria is one of Jordan's biggest Arab commercial partners. The country also serves as a gateway for Jordan's trade with Lebanon, Turkey and Europe, and Damascus has $500 million in deposits in Jordanian banks and multimillion dollar investments in Jordan.

The head of the Arab League, Nabil Elaraby, was in Baghdad Thursday to try to persuade Iraq to use its influence on Syria get Damascus to accept an Arab League peace plan.

Iraqi Foreign Minister Hoshyar Zebari said "the Iraqi government will do its best with the Syrian government in order to remove all obstacles facing the implementation of this noble initiative."

It was not immediately clear whether Iraq's stance toward Syria was changing. Iraq has abstained from two Arab League votes designed to pressure Syria to stop its repression of protesters.