- The U.S. secretary of state accuses Russia of sending attack helicopters to Syria
- The Syrian regime slams the United States, accusing it of supporting "terrorists"
- At least 60 people are killed Tuesday, an opposition group says
- U.N. report: Children are tortured because relatives are suspected of supporting opposition
(CNN) -- The Syrian crisis is now a civil war, a U.N. official said, as the United States accused Russia of sending attack helicopters to the Middle East nation and monitors tasked with observing a so-called cease-fire came under fire.
Meanwhile, the war of words raged on.
Syria accused the United States of "blatant interference," saying the latter is openly supporting terrorists.
"Covering up terrorists' crimes, distorting facts about Syria at the U.N., and extorting countries and the international community to beleaguer Syria," state-run media reported Wednesday.
Peacekeeping chief Herve Ladsous is the first U.N. official to publicly acknowledge a devolution to a civil war.
"Yes, I think we can say that," Ladsous told two news agencies. "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."
His spokesman, Kieran Dwyer confirmed the remarks to CNN, but said labeling the conflict is not what's important.
"Whether we call it all-out civil war ,whether we call it partial civil war, civil war in some places, the point is that it's hugely escalated, that it's across nearly all parts of the country and that the civilians, ordinary Syrian people, are the ones that are suffering," Dwyer said.
Civilians bearing the brunt of the crisis include young children, tortured or used as human shields by the Syrian regime, according to a report released by the United Nations this week.
"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 states, citing dozens of witness 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 says.
It also includes allegations that rebel forces such as the Free Syrian Army recruited and used children, despite its stated policy of not recruiting anyone younger than age 17.
Free Syrian Army officials could not be immediately reached for comment.
Syrian President Bashar al-Assad's regime has long blamed violence in the country on "armed terrorist groups."
A human rights group has implored the U.N. Security Council to impose an arms embargo on Syria. Human Rights Watch said the council should impose targeted sanctions such as asset freezes and travel bans on Syrian leaders.
Citing the Syria Violations Documentation Center, a network of Syrian activists, the group said at least 1,176 children have been killed since February 2011.
At least 60 people were killed across Syria on Tuesday, including many children and women, the opposition Local Coordination Committees of Syria said.
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Struggle to save wounded kids in Syria A family of six, including an infant, was killed in Aleppo province when a shell landed on their home, the LCC said.
The state-run Syrian Arab News Agency, meanwhile, said 36 "martyrs from the army and law enforcement forces" were buried Tuesday.
CNN cannot independently confirm reports of casualties or violence in Syria because the government has restricted access by international journalists.
Residents of the pro-government town of al-Sheer, near al-Haffa, prevented U.N. observers from reaching al-Haffa on Tuesday by laying down on the road, the opposition Syrian Observatory for Human Rights said.
Angry crowds confronted observers trying to reach al-Haffa, in Latakia province, surrounded their cars, and hurled stones and metal rods at the vehicles, the U.N. monitoring mission in Syria said.
As U.N. observers were leaving the area, an unknown source fired at three vehicles headed toward Idlib, they said.
The observers returned to their bases "and are secure," the U.N. statement said. The mission had been trying to reach al-Haffa since Thursday, but has been impeded by ongoing violence in the area, the statement said.
A banner on state-run TV said some residents in the province "tried to explain to members of the observers' mission their suffering from terrorist groups, but the observers did not listen to them. Instead, one of their cars hit three citizens," two of whom were in critical condition.
Ladsous' spokesman called the firing on peacekeepers' vehicles "deliberate and direct," and said U.N. officials were evaluating whether the 300 unarmed peacekeepers in Syria are safe enough to continue their activities.
On Tuesday, U.S. Secretary of State Hillary Clinton expressed concern about reports that Russia may be sending attack helicopters to Syria. Clinton said the United States has confronted Russia about stopping its arms shipments to al-Assad's regime.
State Department spokeswoman Victoria Nuland said the United States has been "pushing the Russians for months to break their military ties with the Syrian regime and they haven't done it. And instead they keep reassuring all of us that what they are sending militarily to Syria can't be used against civilians. And now what are we seeing? We are seeing the Syrian government using helicopters to fire on their own people from the air."
Deputy Secretary of State William Burns will talk with a Russian official to discuss Syria at an economic meeting Thursday in Kabul, the State Department said.
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's Richard Roth, Holly Yan and Salma Abdelaziz contributed to this report.
