TIKRIT - Iraqi forces entered Tikrit Wednesday, dodging bombs and sniper fire in search of their biggest victory yet against embattled militants who tried to light new fires elsewhere in Iraq and Syria.

The Islamic State group has suffered stinging defeats in the heart of its self-proclaimed “caliphate” recently, but its ultraviolent ideology has inspired attacks and recruits globally.

With IS brutality and population displacement reaching new highs, Washington sought increased powers from the US Congress to take on a group threatening to reshape the Middle East.

However, it was without direct support from the US-led coalition’s air campaign that Iraqi government and allied forces punched into parts of Tikrit, marking a new phase in a 10-day drive to wrest the city back from IS.

A combination of army, police and volunteer forces moved into northern and southern Tikrit, the hometown of former Iraqi president Saddam Hussein and a main IS stronghold.

A major general told AFP on condition of anonymity that government forces were battling “to cleanse the neighbourhood of Qadisiyah” in Tikrit.

“But we are engaging in a very delicate battle because we are not facing fighters on the ground, we are facing booby-trapped terrain and sniper fire. Our movement is slow,” he said.

An army colonel said forces coming from another direction had also retaken the main hospital on the city’s southern edge. Early in the offensive, in which up to 30,000 men were initially involved while IS is believed to have just a few hundred men inside Tikrit, most outlying areas were reconquered.

The town of al-Alam, a flashpoint north of Tikrit along the Tigris river, was fully under the control of pro-government fighters and local anti-IS Sunni tribesmen Wednesday, an AFP reporter there said.

On the back foot in eastern and northern Iraq, IS tried to seize the initiative elsewhere, including with a spectacular coordinated attack in Ramadi in the west.

Twelve car bombs exploded almost simultaneously around the city after dawn, with at least seven suicide bombers targeting government security installations, police said.

At least 17 people were killed and 38 wounded, according to a police lieutenant colonel and a doctor at Ramadi hospital. Clashes ensued but IS failed to gain any ground in one of the biggest attacks against a rare pocket of government control in Anbar.

“Our brave security forces were ready and had excellent intelligence about the operation,” Anbar Governor Sohaib al-Rawi said on social media.

Also on the offensive in Syria, the militants launched a “huge assault” Wednesday to try to capture a strategic town on the border with Turkey, killing dozens.

Their attack focused on Ras al-Ain and IS seized a nearby village, the Syrian Observatory for Human Rights said.

Observatory head Rami Abdel Rahman said the offensive was a preemptive strike against Kurdish militiamen planning to attack the IS-held town of Tal Abyad farther west.

At least 12 fighters from the Kurdish People’s Protection Units, which control Ras al-Ain and surrounding villages, were killed, he said.

IS has also ramped up its propaganda war in what some analysts see as a possible sign of desperation by a movement on its last legs.

After destroying several Iraqi heritage sites that are among the planet’s most precious, the militants again shocked the world on Tuesday by releasing a video in which an Arab Israeli accused of spying for Israel is “executed” by a boy who looks no older than 12.

Addressing US lawmakers, Secretary of State John Kerry said it was a “pivotal hour” in the battle against the most violent group in the history of modern jihad.

Appearing before the Senate foreign relations committee, he and top US defence officials appealed for a united vote in favour of a new authorisation for the use of military force against IS.

The United States leads a 60-nation coalition involved in the fight against the militants and has carried out hundreds of strikes against IS in Iraq and Syria.

However, the US security establishment has expressed unease at the prominent role played by Iran in the military effort.

“I am made uncomfortable by the fact that it looked like a Shia advance against a Sunni town,” former CIA chief Michael Hayden said Tuesday of the operation to retake Tikrit.

Iran’s top commander for external military operations, Qassem Soleimani, has been ubiquitous on Iraq’s front lines.

Comments by Iranian-backed militia commanders had stoked fears that the recapture of Tikrit could lead to widespread sectarian reprisal killings.

But so far, reports of abuses by the mostly Shiite Iraqi forces battling IS in and around Tikrit have been relatively limited.

Meanwhile, three London schoolgirls who fled to Syria are believed to have stolen family jewellery to fund their travel, police said Tuesday as the trio’s relatives expressed disbelief at their actions.

Schoolfriends Kadiza Sultana, 16, and 15-year-olds Shamima Begum and Amira Abase, left their homes last month and flew to Istanbul, from where they are believed to have joined Islamic State (IS) militants in Syria.

Giving evidence before parliament’s home affairs committee, Britain’s national police lead on counter-terrorism, Mark Rowley, said the girls paid a travel agent more than £1,000 (1,409 euros, $1,506) for their flights.

Asked where they found the money, he said: “We think it’s linked to theft from families. We think it’s linked to taking jewellery from one of their family members.”

However, family members later said that the girls must have found additional funds elsewhere, as the jewellery that was missing was not of great value.

“We haven’t lost £2000 worth of jewellery,” Shamima’s sister Renu Begum told ITV News.

“I feel there is someone out there helping in terms of funding because there’s no way my sister has got the cash to fund herself,” said Kadiza’s sister Halima Khanom.

“I really hope the police would now make it their business to establish where these funds came from because it clearly wasn’t from home,” added Kadiza’s cousin Fahmida Aziz.

The girls are among 26 British young women who have gone to join IS fighters in Syria, according to Rowley, who is assistant commissioner of London’s Metropolitan Police.

But he said that so far “we have no evidence to suggest they are involved in terrorism”, and they could return home to Britain without facing charges.