The terrorist group, famous for posting online videos of beheadings of innocent victims, now takes depravity to new depths: Children have been executed. And as people flee the violence in Syria, a species faces extinction.
Here are things to know about what is going on now with ISIS -- the Islamic State in Iraq and Syria
-- which seeks to establish a caliphate in the Middle East.
More than 90 people -- including at least 11 children -- have been executed by ISIS fighters in the central Syrian city of Palmyra in the last seven days, the head of the Syrian Observatory for Human Rights told CNN on Sunday.
Many of the people killed were family members of Syrian regime forces or policemen, said Rami Abdurrahman, the observatory's executive director.
About 11,000 people have fled Palmyra and its surrounding villages after ISIS took control of the area, the U.N. Refugee Agency said last week.
Syrian State TV, citing local sources inside Palmyra, reported Sunday that 400 people have been killed in the city as fighting has raged.
ISIS has taken control of the city, and it is feared that the group may now destroy Palmyra's ancient treasures.
Bird faces extinction
It's not only people who suffer in all the violence. The northern bald ibis may become extinct in the wild in Syria, according to a conservation group.
Before Syria's civil war
, the birds faced the threats of climate change, hunting and power lines, said Assad Serhal, general director of The Society for the Protection of Nature.
Now, its human-on-human violence.
When ISIS took over the area near Palmyra, the guards and teams caring for the birds fled.
At one point, there were 11 bald ibises in the area, but the population in Palmyra has been reduced to the three birds -- two males and one female.
They were not moved from captivity near Palmyra is because there is an egg that "we are waiting for to hatch," Serhal said.
"We have just heard from our sources near Palmyra that all three birds and the egg are being kept in a safe place," he said. "We cannot reveal their location,"
The female, Zenobia, is the only bird who knows the migration route to Ethiopia -- Syria over Jordan, then over Saudi Arabia and Yemen to Ethiopia. "She should make the trip at the end of the summer, and we are waiting for her arrival in Ethiopia, hopefully with a hatched bird with her," Serhal said.
"We hope that culture, nature, human beings will prevail above being destroyed by war," he said. But he added, "War prevails above and beyond illegal hunting, climate change and habitat destruction."
Iraq rebuts allegation
The Iraqi Prime Minister has rebutted remarks by the U.S. secretary of defense, who said that the Iraqi military just did not have the determination to fight as the key city of Ramadi fell.
"What apparently happened was that the Iraqi forces just showed no will to fight," Defense Secretary Ash Carter told CNN's Barbara Starr in an interview
that aired Sunday. "They were not outnumbered. In fact, they vastly outnumbered the opposing force, and yet they failed to fight."
But Iraqi Prime Minister Haider al-Abadi told the BBC
he was "surprised" by Carter's remarks, suggesting the defense secretary was "fed the wrong information."
Iraqi forces have launched a counterattack
against ISIS in Anbar province, the Sunni Muslim heartland of Iraq.
Pressed by the BBC for a time frame, al-Abadi said the forces would take back Ramadi, the capital of Anbar, in a matter of days.