Three rockets hit the US embassy in Iraq’s capital on Sunday night – the first direct hit after months of close calls, as thousands of protesters kept up anti-government sit-ins across the country.

Embassy staff said one person was injured in the attack but did not specify the nature of the injuries nor the individual’snationality. They said the rocket hit a restaurant inside the embassy compound.

The embassy is in Baghdad’s Green Zone, and has been a flashpoint amid wider regional tensions between the US and Iran that have played out in Iraq in recent weeks. Iraqi supporters of an Iran-backed militia stormed the embassy compound on December 31, smashing the main door and setting fire to the reception area.

The attack was a serious escalation in the spree of rocket attacks in recent months that have targeted the embassy or Iraqi military bases where American troops are stationed.

None of the attacks has been claimed but Washington has repeatedly blamed Iran-backed military factions in Iraq.

On Sunday, one of the five rockets fired at the heavily fortified compound hit an embassy cafeteria at dinner time while two others landed near by, a security source said.

A senior Iraqi official said at least one person was wounded, but it was not immediately clear whether the person was an American citizen or an Iraqi staff member working at the mission.

Demonstrators block the road with burning tires during ongoing anti-government protests in Nassiriya, Iraq. REUTERS A protester is helped after Riot police fired tear gas during clashes with anti-government protesters in Baghdad. AP Photo An anti-government protester prepares to throw a molotov cocktail toward security forces during clashes with anti-government protesters in Baghdad. AP Photo Riot police fire tear gas to disperse anti-government protesters during clashes with anti-government protesters in Baghdad. AP Photo An anti-government protester throws back a tear gas canister fired by riot police during clashes with anti-government protesters in Baghdad. AP Photo An Iraqi protester reacts to tear gas fired by security forces during clashes with anti-government protesters in Baghdad. AP Photo Security forces try to disperse anti-government protesters during clashes with anti-government protesters in Baghdad. AP Photo Iraqi soldiers inspect the wreckage of protesters' tents at the protest site in Basra. EPA An Iraqi soldier stands guard next to the wreckage of protesters' tents at the protest site in Basra, southern Iraq. EPA A demonstrator shows the casings from bullets and a tear gas canister which were allegedly used by the Iraqi security forces during ongoing anti-government protests in Baghdad. REUTERS Security forces fire tear gas during clashes with anti-government protesters in Baghdad. AP Photo A demonstrator receives medical help after being affected by tear gas during ongoing anti-government protests in Baghdad. REUTERS

The US embassy did not immediately respond to requests for comment.

On Sunday the US State Department called on Iraq to “fulfil its obligations to protect our diplomatic facilities”.

The attack took place earlier in the day than usual, with explosions echoing over the western bank of the River Tigris at precisely 7.30pm local time.

Iraqi Prime Minister Adel Abdul Mahdi and Speaker of Parliament Mohammed Halbousi both condemned the incident, saying it risked dragging their homeland into war. Iraq’s foreign ministry rejected the attack and said it would take all necessary action to protect diplomatic missions in the country. The ministry said the attack had “not affected relations between Baghdad and Washington”.

Militia leader Hadi Al Amiri said the attack was aimed at forcing foreign troops out of the country.

Iraq has already been dragged into a series of retaliatory exchanges between the US and Iran over the past month.

A similar attack on a northern Iraqi base killed an American contractor, and the US retaliated with a strike on an Iran-backed faction known as Kataib Hezbollah.

Less than a week later, a US drone strike killed Iranian general Qassem Suleimani outside the Baghdad airport – prompting Iran to fire ballistic missiles at an Iraqi base where US troops are stationed.

Some 5,200 Americans are stationed in Iraq to lead the global coalition fighting the ISIS militant group, but the US strike on Baghdad has rallied top Iraqi figures around a joint call to order them out.

Vehemently anti-American cleric Moqtada Al Sadr organised a mass rally in Baghdad on Friday, where thousands of his supporters called for American troops to leave.

Mr Al Sadr had previously backed separate anti-regime protests sweeping Iraq's capital and south, even though he controls the largest bloc in parliament and top ministerial posts.

But the populist cleric cancelled a planned demonstration against the US on Sunday "to avoid internal strife" but gave few other details.

Bolstered by a previous protest on Friday, Mr Al Sadr announced he was dropping support for the youth-dominated reform campaign rocking the country since October.

Many of his followers, widely regarded as the best-organised and well-stocked of the anti-government demonstrators, immediately began dismantling their tents and heading home.

Activists feared that without his political cover, authorities would move to crush their movement – and indeed, within hours, riot police tried to storm protest camps.

Those efforts continued into Sunday, with security forces using live rounds and tear gas to try to flush protesters out of squares and streets they had occupied for months.

One protester was shot dead in Baghdad and another in the flashpoint southern city of Nasiriyah, medical sources said, and dozens more were wounded across the country.

In the capital, riot police have tried to clear streets around the main protest camp of Tahrir Square but have yet to enter the symbolic area, where many protesters stood their ground even after tents there were dismantled.

Just after midnight in Nasiriyah, unknown assailants stormed the main protest camp in Habbubi Square and set the tents on fire, the flames lighting up the night sky.

Despite the renewed violence, thousands of students flooded the streets in the capital and across the south in a bid to keep national attention focused on their demands.

"Only for you, Iraq!" read a sign held by a young protester in the shrine city of Karbala, hinting at the movement's insistence on not being affiliated with any political party or outside backer.

In Basra, hundreds of students gathered to condemn the riot police's dismantling of their main protest camp the previous day.

The youth-led protests erupted on October 1 in outrage over lack of jobs, poor services and rampant corruption before spiralling into calls for a government overhaul after they were met with violence.

More than 470 people have died, a vast majority of them demonstrators, since the rallies began.

Protesters are now demanding snap elections, the appointment of an independent premier and the prosecution of anyone implicated in corruption or recent bloodshed.