The US military offensive in Iraq escalated sharply yesterday as 10,000 American troops launched a another offensive against Sunni insurgents and al-Qaeda jihadis in Diyala province, northeast of Baghdad.
At least 22 insurgents were reportedly killed in initial clashes as US forces moved into the western suburbs of Baquba, the provincial capital. US commanders claim up to 500 al-Qaeda fighters were holed up there.
Even as US forces advanced, insurgents behind the lines detonated a devastating truck bomb at a Shia mosque in the centre of Baghdad. Early reports said at least 78 people were killed and 224 wounded.
The mosque's imam, Sheikh Saleh al-Haidari, said civilian worshippers had been targeted in the blast as they left afternoon prayers. He blamed the attack on "sick souls".
In all, 2,000 insurgents are said to have moved to Diyala from Mosul, Anbar and Baghdad in recent months as US forces tightened their grip in those areas.
The ground offensive, which also encompassed parts of western Anbar province and was mounted before dawn with Bradley fighting vehicles and air support, coincided with intensifying US-led operations in southern Iraq.
The primary coalition target in the south appeared to be Shia militia strongholds and forces loyal to radical cleric Moqtada al-Sadr, a long-time foe who returned from hiding recently to demand an end to western occupation.
Fierce fighting, pitting elements of al-Sadr's Mahdi army against US, British and Iraqi troops was reported in Amara and Majjar al-Kabir, north of Basra, and in Nasiriya, southeast of Baghdad. At least 30 people have died and some 150 have been injured in the past two days.
Officials in Basra said the assault on the Mahdi army, the biggest since the surge began in February, appeared to be the beginning of a long-anticipated American push to reduce al-Sadr's power and the influence of his Iranian sponsors.
The US military indicated that yesterday's offensive around Baquba, codenamed Operation Arrowhead Ripper, was the beginning of an open-ended engagement against insurgents displaced from Baghdad in recent months. "We are going into the areas that have been sanctuaries of al-Qaeda and other extremists to take them on and weed them out," a spokesman said.
Maj Gen Abdul-Karim al-Rubaie, commander of Iraqi forces in Diyala, claimed that torture devices, including handcuffs, electric cables and swords, had been found in safe houses vacated by fleeing insurgents.
President George Bush ordered 30,000 additional troops to Iraq last January in what was seen then as a desperate attempt to secure Baghdad and surrounding areas, and give Iraqi government institutions a chance to function.
Democrats and other opponents of the war in Washington say time is running out, with Senate leader Harry Reid declaring recently that the war was already lost. A Pentagon report last week concluded the surge had failed so far to reduce overall levels of violence.
The twin offensive mounted in the north and south appears to be Mr Bush's answer, and that of his senior commander Gen David Petraeus, to the critics at home.
Mr Bush is also redoubling political and diplomatic efforts to turn around the situation in Iraq before what many see as a September deadline for a decision on whether to continue the surge or begin a phased withdrawal.
In recent days the White House has sent a stream of senior envoys to Baghdad, including defence secretary Robert Gates, all demanding faster progress on political reforms.
Mr Bush spent almost an hour on Monday in a teleconference with Iraq's prime minister, Nuri al-Maliki, and other Iraqi leaders. His spokesman said the president was "reassured" by what he heard, but declined to say why.
The effect of the Iraq crisis on the domestic front again emerged yesterday as news broke of an embarrassing dispute between the state department and US ambassador to Iraq Ryan Crocker over the quality of US staff assigned to Iraq.
"We cannot do the nation's most important work if we do not have the department's best people," Mr Crocker complained in a memo obtained by the Washington Post.