Story highlights U.S. worried about sectarianism in Iraqi forces, sources tell CNN

Report: Militants left a message, "This is the fate of any prostitution"

Residents say Shiite group carried out attack, but it denies having forces in Baghdad

Car bombings kill two in Baghdad; roadside bomb targets a Kurdish police convoy

An attack on apartments that neighbors say were used as a brothel in Baghdad has killed at least 28 women and six men, security officials told CNN.

Unidentified militants wearing military uniforms and street clothes stormed apartments Saturday in the Zayona residential complexes in eastern Baghdad, officials said. They fired their weapons in the streets before breaking down doors to enter the buildings, security officials and residents told CNN. Once inside, they killed the men and women, officials said.

Attackers left a message on a door: "This is the fate of any prostitution," an Agence France-Presse correspondent on the scene reported.

Residents told CNN the Shiite Asa'b Ahl al-Haq organization carried out the attack. But the organization told CNN it does not have forces inside the city.

There was no letup in violence Monday, with two car bombs in Baghdad and a roadside bomb in Iraqi's semiautonomous Kurdish region. There were also ongoing clashes in Salaheddin province, 70 kilometers (about 44 miles) north of the capital.

Two people were killed and 14 others wounded in the separate car bombings in the al-Bayaa and al-Alawi areas of Baghdad, police officials said.

Meanwhile, a roadside bomb targeted a Kurdish police convoy patrolling a road between Sulaimaniya and Diyala provinces, killing one police officer, Kurdish Peshmerga officials told CNN. The area is controlled by the Peshmerga Kurdish fighters.

In Salaheddin province, fighting between militants from the Islamic State of Iraq and Syria, or ISIS, and Iraqi forces backed by Sunni al-Jubouri tribesmen broke out late Saturday in Dhuluiya, police officials and a tribal representative told CNN. ISIS controls 50% of the town, including the mayor's office, municipal council and the police building, they said.

Six security force members and tribal fighters have been killed in the fighting.

ISIS, an al Qaeda splinter group, has led Sunni insurgents who have taken over large areas of northern and western Iraq in an offensive that began last month. The terrorist group has also made major gains in Syria in its quest to establish an Islamic state spanning both countries.

"ISIS terrorist groups started shelling the town with mortars from the northern side of the town," the al-Jubouri spokesman said, before pickup trucks loaded with armed militants moved in to occupy government buildings.

A YouTube video purportedly from ISIS shows militants raising a flag over the buildings.

"We are steadfast and will cleanse the town from them in 48 hours," the al-Jubouri spokesman said.

U.S. report on Iraqi readiness

The initial U.S. military assessment of Iraqi security forces ordered by U.S. President Barack Obama was given Monday to Defense Secretary Chuck Hagel and Gen. Martin Dempsey, chairman of the Joint Chiefs of Staff, a Pentagon spokesman said.

Pentagon officials will review the report -- which assesses the capabilities, training, morale, leadership, and command and control of Iraq's forces -- before giving the President recommendations for the next steps in supporting Iraq's forces.

Pentagon press secretary Rear Adm. John Kirby said the United States has "not moved to an advisory capacity at this point."

Two U.S. officials tell CNN a major concern that has been raised is the overwhelming sectarianism in Iraqi forces. In particular, U.S. commanders are concerned if they move into a direct advisory role of Iraqi government forces, it will be perceived as taking sides with the Iranian-backed Shiite elements inside Iraqi units.

U.S. military personnel are also looking at why so many Iraqi units collapsed in the face of the initial ISIS advances and whether it is possible to even reconstitute those units to the point that U.S. advisers would be useful.

The officials also said that if Baghdad was attacked, Iraqi forces would need help from Iranian-backed militia.

Another concern is infiltration of Iraqi units by militants and potential green-on-blue attacks -- that is, attacks on U.S. personnel by members of the Iraqi forces.

Kirby would not say what was in the report but noted, "This is a lesson that certainly we learned in recent years from Afghanistan. We always keep in mind and have to keep in mind the insider threat, and we have to factor that in when we are doing work in a partnership capacity n a situation such as this, where it's as dangerous as it is."

President Obama has authorized 300 military advisers in Iraq, 210 of which are there now.

ISIS success in Syria

ISIS also has been making gains in Syria. In the eastern Syria city of Deir Ezzor, militants took control of areas that had been held by other rebel groups, such has al-Nusra Front and the Free Syrian Army, the UK-based opposition group Syrian Observatory for Human Rights said.

The other rebels either left the city or pledged allegiance to ISIS, the observatory said. That means the city is controlled partly by the government and partly by ISIS. Deir Ezzor is 100 kilometers (62 miles) east of the Iraqi border.

ISIS now controls about 95% of greater Deir Ezzor province, which borders Iraq, the observatory said.

In other violence over the weekend in Iraq, militants believed to be with ISIS attacked the city of Haditha from four directions, said Hameed Ahmed al-Hashim, a member of the Anbar provisional council, and two security officials in Haditha.

A large military force backed by tribesmen defended the city, they said.

Iraqi jet fighters bombed a bridge controlled by militants east of Falluja, causing structural damage, al-Hashim said.

Three police officers were wounded when a roadside bomb exploded near their convoy in Kirkuk, a security official told CNN on Saturday.