Syrian army deserters killed eight people in an attack on an intelligence building in the north of the country, an opposition group said on Friday.
It said the attack took place on Thursday in Idlib province, between the towns of Jisr al-Shughour and the Mediterranean city of Latakia.
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"A group of army defectors ... attacked the Air Force Intelligence centre," the British-based Syrian Observatory for Human Rights said. "A clash ensued for three hours which lead to the death of at least eight members of the Air Force Intelligence".
The Observatory and other activists also said at least 20 civilians were killed by Syrian security forces across the country on Thursday, mainly in the provinces of Hama and Homs.
UN High Commissioner for Human Rights Navi Pillay said on Thursday that Syria is now in a state of civil war with more than 4,000 dead and increasing numbers of defecting soldiers taking up arms against the government of President Bashar Assad.
"I have said that as soon as there were more and more defectors threatening to take up arms, I said this in August before the Security Council, there was going to be a civil war. At the moment that's how I am characterising this," she said.
Earlier Thursday, the US Treasury Department imposed sanctions against two Syrian officials and two firms for supporting the Syrian government and urged more pressure to bring an end to violence against protesters.
Also on Thursday, it was reported that Russia has delivered supersonic cruise missiles to Syria despite the violence shaking the Arab country.
"The Yakhont supersonic anti-ship cruise missiles have been delivered to Syria," a military source told the Interfax news agency without disclosing when the shipment was made.
Russia signed a contract reportedly worth at least $300 million (222 million euros) in 2007 to supply its traditional Arab world ally with a large shipment of the cruise missiles.
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