BAGHDAD, Iraq (CNN) -

Iraqi lawmakers worked Thursday to organize the process for forming a new government -- with encouragement from the United States and Britain -- while a military spokesman said security forces defended the Baiji oil refinery and the University of Tikrit. Also Thursday, a bomb killed 19 people in a Shiite neighborhood in Baghdad.

Here are the latest developments:

Fight for Haditha Dam

A large number of ISIS fighters and allied militants attacked Haditha in Anbar province on Thursday from two directions, but Iraqi forces backed by Sunni tribesmen repelled the attack, Haditha's police chief said.

The Haditha Dam, which has been described as an ISIS target, is being held by the 7th Division of the Iraqi forces as well as SWAT and helicopters, the police chief said.

Tanks and armored vehicles have also been positioned around the dam, he said.

If something happens to the dam and the floodgates are opened, it could be devastating to the area, the police chief said.

Iraq's Ministry of Interior said on its website that Iraqi forces killed 20 ISIS fighters in Haditha. It did not provide any evidence to support the claim.

Baghdad blast

A bomb blast in northern Baghdad's Kadimiyah neighborhood has killed 19 people and wounded 41 on Thursday evening, police officials told CNN.

The explosion occurred after 6 p.m. local time near the Imam Musa al-Kadhim shrine in the predominantly Shiite neighborhood.

There were conflicting reports as to whether the explosion was caused by a suicide bomber or car bomb.

Diplomats: U.S. airstrikes unlikely before new government

The Obama administration is unlikely to undertake any military strikes against the Islamic State in Iraq and Syria, or ISIS, in Iraq before a new government is formed, senior U.S. officials and Arab diplomats told CNN.

The administration is careful not to publicly, or even privately, demand that Prime Minister Nuri al-Maliki step down, insisting that Iraqis themselves must determine who will be in the government.

But senior U.S. officials and Arab diplomats say they see al-Maliki's ouster as a foregone conclusion, as his inability to gain enough votes will eventually prompt his Shiite-led party to put forth another candidate whom the country's Sunni and Kurds will accept.

Zebari: 'Nobody has control over border points'

Iraq's foreign minister told CNN's Hala Gorani that "nobody has control over the border points."

Asked whether he was comfortable with Syria taking unilateral action and bombing targets inside Iraq with or without warning, Foreign Minister Hoshyar Zebari said: "Well, not comfortable of discomfortable, really, this is the reality. Nobody has control over the border points."

He said the Iraqi side "is trying very hard to reassert its control, but the Syrians have also found an opportunity to reassert they are still there, they still (have) air power to bomb these insurgents and these terrorists.