(CNN) -- The new normal in Syria's civil war involves mass killings, torture and sexual violence, the United Nations said Monday.
Scores of people were reported dead in the latest reports of fighting between rebels and government forces in several cities, including Aleppo, where an embedded journalist revealed her view inside a recent street battle.
Journalist Tracey Shelton was covering the Noor Den al-Zenke rebels, who, like countless comrades across Syria, hope to win democratic reforms against the nation's decades-old regime.
She spent hours with the rebels as they guarded a small patch of occupied street that had become a kind of makeshift home. They had set up lounge chairs and made tea in the middle of the street, said Shelton, a senior correspondent for Global Post.
Journalist details recent bloody street clashes in Aleppo
At least 110 people were killed Monday, an opposition group says
Referral to the International Criminal Court is needed, she says
Killings and torture are now "the norm" in Syria, U.N. human rights chief says
Lookouts were posted at each street corner. They listened for snipers and approaching troops or tanks.
"When the assault came, it came with little warning," she said. A tank appeared in the street and fired at the rebels. Smoke from the clashes engulfed the street.
"We ran back from the tank and waited for the others to escape through the dust and debris," she said. "But no one came."
In that split second, "three men were reduced to broken, bleeding masses."
A few minutes later, a vehicle came to collect the bodies. "The survivors washed away the blood and flesh in a heartbreaking clean-up," she said.
New fighters came to replace their comrades at their posts. "And the battle continued."
Shelton's powerful photos of the clashes reveal the graphic details at the street level of a conflict that has attracted global attention at the United Nations.
U.N. human rights chief Navi Pillay said Monday that mass killings and torture have become "the norm" in Syria since anti-government protests started in March 2011. Rapes and sexual violence against women, men and children are being reported, she said.
With 2.5 million people in urgent need of humanitarian assistance and the government showing no sign of halting the violence, it's time for the case to go to the International Criminal Court, Pillay said.
"A referral will make it abundantly clear to all actors in Syria that they will not escape justice and will be held accountable for alleged violations of international human rights law and international humanitarian law," Pillay said, reiterating her call for the ICC to be involved.
The following are key developments in the country Monday:
On the ground
At least 110 people were killed, including 71 in the Damascus area, the opposition Local Coordination Committees of Syria said.
The toll includes 36 people who were executed in the Damascus suburb of Mouadamiyeh, the group said.
On Sunday, 160 people were killed, including 17 children and 11 women, the LCC said.
Syria, meanwhile, said that 30 civilians, including women and children, were killed and 64 others were wounded Sunday in a "terrorist bombing" in Aleppo.
The attack took place in front of al-Hayat hospital, state-run news agency SANA reported Monday.
A car designed to transport food was rigged with explosives and left a deep crater after the blast, the report said.
Separately, another blast in Aleppo killed three people, including a 10-year-old girl, and wounded six other civilians, SANA said.
The government said its forces inflicted "heavy losses" on "terrorists" and released 30 people who had been kidnapped by terrorist groups.
U.N. and Arab League envoy Lakhdar Brahimi said Monday that he will head to Damascus in a few days to meet with Syrian officials.
In Cairo, where he was meeting with Arab League officials, Brahimi said he is "fully aware" that his mission is "extremely difficult."
When asked whether he will meet with Syrian President Bashar al-Assad, Brahimi responded, "I have hope I will, but I don't know before I will get to Damascus."
United Nations meets
Pillay spoke at a meeting of the U.N. Human Rights Council focused on Syria.
"Human rights abuses are rampant and have reached the point where mass killings, summary executions and torture are the norm," she said.
She called for an end to supplying ammunition to both sides of the conflict.
Reports that homes in Damascus were being bulldozed "may well amount to collective punishment and constitute a war crime or a crime against humanity," Pillay said.
She called for an investigation into killings in Daraya, which "deeply shocked" her.
"Both government and opposition forces deploy snipers who target civilians," Pillay said.
"As time has passed, opposition forces have also been increasingly implicated in kidnappings and abductions, including of foreigners perceived as being government supporters."
Delivery of humanitarian assistance "is hampered by the worsening security situation," she added.
She said she agrees with Brahimi that his job "appears at this point to be close to impossible."
Syria denounces Iraq violence
Syria, meanwhile, slammed a series of attacks that killed dozens Sunday in Iraq.
"The Ministry of Foreign Affairs assures that these terrorist attacks that aim to destabilize the security and stability of brotherly Iraq and the killing of innocent Iraqis without discrimination, will not succeed to return Iraq backwards and cannot affect the solid will of the Iraqi people in moving forward in the advancement of their country and to establish stability," Syrian Foreign Ministry spokesman Jihad Makdissi said in a statement.