British ambassador: Baghdad warned repeatedly

Britain's ambassador to Iraq says Prime Minister Nuri al-Maliki's government was warned repeatedly over the past several months about the threat posed by the Islamic State of Iraq and Syria.

"The fact that Mosul was vulnerable was known," Ambassador Simon Collis said on CNN's Amanpour show.

"The fact that ISIL were already holding territory from last year in parts of western Iraq, in Anbar, and elsewhere was well known."

Collis said Britain's message to al-Maliki's government was always the same: "Any comprehensive counterterrorism strategy would need a political line of operation, an economic and development line of operation, as well as of course security operations."

He continued, "And without that kind of comprehensive approach, it will be impossible to defeat an organization like ISIL."

ISIS is also referred to as the Islamic State of Iraq and the Levant.

Iraqi general killed

The commander of the Iraqi Army's 6th Division was killed in a battle on Monday, according to a statement released by the Prime Minister's office.

He was identified as Gen. Nagm Abdullah Ali. The statement did not detail how he died.

But Atta is quoted by Iraqi news organizations as saying he was killed in shelling in Ibrahim Bin Ali, a Sunni-dominated village about 16 miles north of Baghdad.

CNN could not independently confirm the claim.

Digging in around Baghdad

A commercial airliner roars overhead as one of the thousands of fighters who have taken up arms to protect the Iraqi capital digs into a position a few miles from Baghdad International Airport.

Every 500 feet (150 meters), another fighter armed with an AK-47 assault rifle takes up another position about 2 miles (3 kilometers) from the airport perimeter.

This is the first line of seven similar concentric lines of defense between the outskirts of the capital and the airport, widely believed by Iraqi and U.S. officials to be a top target of ISIS.

The fighters are members of the Badr Brigade, the Iranian-trained militia of the Supreme Council for the Islamic Revolution in Iraq, a powerful Shiite political party in Iraq.

And they are officially taking up arms for the first time in more than a decade, reinforcing Iraq's military.

It was just one of the signs Monday of stepped-up security in and around Baghdad amid fears that ISIS fighters and allied Sunni insurgents already inside the city will launch attacks, such as a bombing campaign.