Suspected Islamist extremists detonated a car bomb near government offices in Aleppo today, killing two and wounding 30.
The blast next to the Political Security Directorate in the city's central neighbourhood of Suleimaniyeh was the second attack in two days on cities where the National Progressive Front government enjoys strong support.
Three suicide bombings in Damascus on Saturday killed 27 people.
No-one has claimed responsibility for any of the terrorist attacks.
A report by the Sana state news agency blamed the latest atrocities on Western powers and their allies in the Middle East, saying that they were "part and parcel of targeting the Syrian people in its security and stability."
It pointed to the "recently witnessed escalation by regional and international parties which was lately manifested in public calls for sending arms to Syria."
Some rebel leaders accused the government of orchestrating the attacks to tarnish the opposition.
The last major suicide bombing in Aleppo was on February 10, when twin blasts struck security compounds and killed 28 people. Damascus has suffered half a dozen suicide bombings since December, most hitting intelligence and security buildings.
In the latest Damascus attack on Saturday two suicide bombers detonated cars in near-simultaneous strikes on heavily guarded intelligence and security buildings, killing at least 27 people.
The explosions struck the heavily fortified air force intelligence building and the criminal security department, several miles apart, at approximately the same time, the Interior Ministry said.
Much of the facade of the intelligence building appeared to have been ripped away in Saturday's attack.
Sana said a third blast went off near a military bus at the Palestinian refugee camp of Yarmouk in Damascus, killing the two suicide bombers.
The government has told international envoy Kofi Annan in a letter that it is "keen to end violence" but insists that armed opposition groups give up their weapons first.
The Syrian letter asks Mr Annan, the joint UN-Arab League envoy, "to provide guarantees to the Syrian government that the armed groups will cease all armed aggressions and give up their weapons to the dedicated authorities in exchange for a full pardon."
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