- NEW: A top U.N. official says Syria is now in a civil war
- Pro-government crowds surrounded U.N. vehicles, threw stones, U.N. says
- 45 people were killed Tuesday, opposition group says; Syria reports 36 "martyrs" buried
- U.N. report: Children tortured because relatives suspected of supporting the opposition
(CNN) -- The Syrian regime has used children as human shields and tortured youths whose parents are suspected dissidents, according to a U.N. report.
The report on children and armed conflict detailed harrowing accounts of juveniles allegedly abused by pro-government forces.
News of the report came as a top U.N. official said the conflict in Syria has spiraled into a civil war.
"Yes, I think we can say that," U.N. peacekeeping chief Herve Ladsous said when asked if Syria is now in a civil war. "Clearly what is happening is that the government of Syria lost some large chunks of territory, several cities to the opposition, and wants to retake control."
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McCain: U.S. reaction to Syria shameful Ladsous made the remarks to two news agencies; his spokesman Kieran Dwyer confirmed them to CNN. Ladsous was not available for comment Tuesday because he was traveling.
The U.N. report about children, dated late April, was released by the United Nations on Monday.
"Most child victims of torture described being beaten, blindfolded, subjected to stress positions, whipped with heavy electrical cables, scarred by cigarette burns and, in one recorded case, subjected to electrical shock to the genitals," the report stated, citing dozens of eyewitness accounts. "... Children were detained and tortured because their siblings or parents were assumed to be members of the opposition or FSA, or they themselves were suspected of being associated with FSA," a reference to the rebel Free Syrian Army.
Dozens of children between ages 8 and 13 were reportedly used as human shields by pro-regime forces during a raid on the village of Ayn l'Arouz in March, the report said.
It also included allegations that rebel forces such as the Free Syrian Army had recruited and used children, despite the FSA's stated policy of not recruiting any child under age 17.
Free Syrian Army officials could not immediately be reached for comment.
Mark Lyall Grant, British ambassador to the United Nations, told CNN the U.N. report's findings are "very disturbing" and will be looked at "carefully by all members of the Security Council. But it's just yet another chapter in the barbarity that is being imposed by the Syrian regime on its own civilian population.
"So to be honest, we are not surprised by the report, but it is still abhorrent example of how far beyond the pale of humanity the Syrian regime has gone."
The Syrian regime has long blamed violence in the country on "armed terrorist groups."
The country on Tuesday lashed out at the United States. A report from the state-run news agency SANA cited an "official source" at the Syrian Foreign Ministry saying "that the U.S. administration is continuing its blatant interference in the internal affairs of Syria, its open support for terrorists, covering up terrorists' crimes, distorting facts about Syria at the U.N., and extorting countries and the international community to beleaguer Syria."
U.S. officials have assailed Syria's brutal crackdown on the opposition, as well as its claims that terrorists are to blame for the violence.
A human rights group has implored the U.N. Security Council to impose an arms embargo on Syria "in response to widespread killings and other grave violations against children."
Human Rights Watch said the council should impose targeted sanctions such as asset freezes and travel bans on the Syrian leadership.
The group said at least 1,176 children have been killed since February 2011, citing the Syria Violations Documentation Center, a network of Syrian activists.
After 15 months, the bloodshed shows no sign of letting up, as regime forces continue shelling cities across the country, opposition activists say.
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Syria: Torture, threshold for war crimes At least 45 people were killed Tuesday, including many children and women, the opposition Local Coordination Committees of Syria said. Sixteen of the dead were in Deir Ezzor, and 10 were in Homs, the group said.
Residents of the pro-government town of al-Sheer, near al-Haffa, prevented U.N. observers from reaching al-Haffa on Tuesday by creating a human shield along the road that passes though their town, the opposition Syrian Observatory for Human Rights said.
The residents lay down along the road, so the observers went back and looked for other roads to take, the observatory said.
The U.N. Supervision Mission in Syria said in a statement that observers trying to reach al-Haffa, in Lattakia province, "were confronted with angry crowds that surrounded their vehicles, stopping them from proceeding any further. The crowd, who appeared to be residents of the area, then hurled stones and metal rods at the UN vehicles.
"The U.N. observers turned back. As they were leaving the area, three vehicles heading towards Idlib were fired upon. The source of fire is still unclear."
The observers are back at their bases "and are secure," the U.N. statement said. The mission has been trying to reach al-Haffa since Thursday but has been impeded by ongoing violence int he area, the statement said.
U.N. and U.S. officials have expressed concerns about reports of the government using mortars, helicopters and tanks against the opposition in al-Haffa. They've also expressed concerns that residents might be "trapped."
A banner on state TV said that some resident in Lattakia province "tried to explain to members of the observers' mission their suffering from terrorists groups, but the observers did not listen to them. Instead, one of their cars hit three citizens," two of whom are in critical condition.
Meanwhile, Syria said an "armed terrorist group" attacked the state-run al-Ikhbaria TV channel in al-Haffa in "an attempt to stop national media from conveying the truth." The report said the channel was reporting "objectively and responsibly."
The group opened fire on a car, and "al-Ikhbaria correspondent Mazen Mohammad was hit in his hand while cameraman Fadi Yakoub was hit in his chest," state-run news agency SANA reported.
SANA also reported that 36 "martyrs from the army and law enforcement forces" were buried Tuesday.
The latest reports of violence came a day after government forces fired indiscriminately from helicopters on a town on the outskirts of Jabal Al-Zawiya, inflicting scores of casualties among civilians and rebel forces, an activist told CNN.
Ibrahim Swed, speaking from the Idlib province town, said fighting between the Free Syrian Army and government forces persisted for six hours and resulted in 32 deaths.
Opposition activists said at least 93 people were killed across the country Monday, including 35 in Idlib.
"The regime is escalating the use of violent forces," said an activist in Idlib whom CNN is identifying only as Ahmad for safety reasons. "We cannot believe that the world is watching us being killed ... we want military intervention."
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U.S. State Department spokeswoman Victoria Nuland said the attacks indicated the government's desperation.
The use of helicopters to fire on civilians and the use of pro-regime thugs called Shabiha constitute "a very serious escalation," Nuland told reporters.
"What government voluntarily uses helicopters and fires from them on their own civilians if they're not desperate?" she asked. "What government depends on a bunch of thugs in trucks, irregulars, if they're not desperate? ... Clearly, the government is under threat."
U.N.-Arab League special envoy Kofi Annan said he was "gravely concerned" about reports that fighting between Syrian government and opposition forces had escalated.
"He is particularly worried about the recent shelling in Homs as well as reports of the use of mortars, helicopters and tanks in the town of al-Haffa, Lattakia," Annan spokesman Ahmad Fawzi said in a statement Monday. "There are indications that a large number of civilians are trapped in these towns."
Nuland said U.N. military observers had been trying to reach al-Haffa but had been blocked by government forces.
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The United Nations estimates that more than 10,000 people, mostly civilians, have died since the crisis erupted in March 2011. Opposition groups give estimates ranging from at least 12,000 to more than 14,000.
CNN cannot independently confirm reports of casualties or violence in Syria, as the government has restricted access by international journalists.
CNN's Holly Yan, Salma Abdelaziz and Hamdi Alkhshali contributed to this report.
