(CNN) Eight police officers and an immigration officer were killed during a series of coordinated attacks against police in Myanmar's western Rakhine State, authorities said Friday.

At least 20 police outposts and an army base were targeted, the committee said. Authorities alleged that an estimated 150 insurgents attempted to storm the base but "soldiers fought back."

The bodies of 16 insurgents have been recovered, the State Counselor Office's Information Committee said on Facebook.

"Fighting remains in some locations and a combined forces of the Tatmadaw (Myanmar armed forces) and police forces are still waging an attack against the extremist terrorists," the committee said.

The violence erupted hours after the release a long-awaited report into the treatment of Rohingya by the Advisory Commission on Rakhine State, led by former United Nations Secretary-General Kofi Annan.

The report warned unrest in the state could spiral out of control unless concrete action is taken soon. "Tensions remain high and they risk becoming worse," Annan said. "The status quo cannot continue."

The attack was significantly bigger than one in October 2016, which sparked the latest round of unrest in Rakhine State, according to Human Rights Watch Deputy Asia Director Phil Robertson.

"This was a significant attack," Robertson told CNN. "Clearly, it doesn't help to have the security issue come right up front again so soon after the launch of the report."

Claim of responsibility

An insurgent group known as the Arakan Rohingya Salvation Army, formerly known as Harakat al-Yaqeen -- or "Faith Movement" -- claimed responsibility for the attack on Twitter.

"This is a legitimate step for us to defend the world's persecuted people and liberate the oppressed people from the hands of the oppressors!" the group said.

Rakhine State is home to Myanmar's Rohingya community, ethnic Muslims who have long faced persecution in the Buddhist-majority country, especially from the country's Buddhist extremists.

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The Rohingya are not formally recognized as citizens -- the Myanmar government does not even use the term Rohingya, referring to the group as "illegal immigrants" from neighboring Bangladesh, a Muslim-majority country .

The majority of Rohingya have been in Myanmar for multiple generations. State media has published columns in which Rohingya "terrorists" are referred to as "detestable human fleas."The majority of Rohingya have been in Myanmar for multiple generations.

Government operations

Violence in Rakhine State has occurred in fits and starts in recent years, with the latest outbreak beginning in the wake of numerous attacks by militants on several government border posts in October 2016.

Who are the Rohingya? The Rohingya are a stateless Muslim minority in Myanmar's Rakhine state thought to number about 1 million people.

Myanmar does not recognize them as citizens or one of the 135 recognized ethnic groups in the country.

Myanmar regards them as illegal immigrants, a view rooted in their heritage in East Bengal, now called Bangladesh.

Though many Rohingya have only known life in Myanmar, they are widely viewed as intruders from across the border.

According to Human Rights Watch, laws discriminate against the Rohingya, infringing on their freedom of movement, education and employment.

They are denied land and property rights and ownership, and the land on which they live can be taken away at any given time.

The Myanmar military responded with a series of security operations to find what it claimed were terrorists hiding among the Rohingya population.

Thousands fled across the border to neighboring Bangladesh, where refugees told stories of their villages being burned, mothers and daughters being raped and friends being summarily executed.

Yanghee Lee, a UN special rapporteur told CNN in March that crimes against humanity may have been committed.

"When there's 77,000 people running away from their home towns, leaving everything ... the international community should really step up to the plate," she told CNN.

The government has denied many of the allegations leveled against the military -- including those of human rights abuses -- and says it's investigating others. The charges are difficult to corroborate, as most international media and aid organizations have been heavily restricted from traveling to the region.

Commission findings

The Rakhine Advisory Commission was set up last year to analyze the situation in Rakhine State and issue recommendations. Its findings were published Thursday.

"Unless concerted action -- led by the government and aided by all sectors of the government and society -- is taken soon, we risk the return of another cycle of violence and radicalization, which will further deepen the chronic poverty that afflicts Rakhine State," Annan said upon announcing the commission's finding.

The commission recommended, some of which include:

Ensure full and unimpeded humanitarian access to the region as well as full and regular media access. Ensure freedom of movement for all people of Rakhine State, regardless of religion, ethnicity and citizenship. Abolish different types of citizenship and re-examine links between citizenship and ethnicity. Ensure that all verified citizens of Myanmar enjoy the all the benefits associated with citizenship. Clarify the status and rights of people living in the country that aren't citizens, including those who are stateless. Plan to close internally displaced persons camp and help people return in a voluntary, safe and dignified manner. Encourage local participation in decision making and state development Invest in infrastructure

Human Rights Watch and other humanitarian groups lauded the recommendations.

"The Commission has developed an impressive set of common-sense, focused recommendations that if fully implemented could bring the sort of progress that has been missing in Rakhine State for decades," Roberston said.

But the rise of ARSA, the first Rohingya group to take up arms in decade, has fueled worries that extremists on both sides could further damage the situation -- making the report's implementation all the more urgent said Robertson.

"We're going to see these kind of flare-ups and efforts by extremists on all sides to try to derail these recommendations," he said.

Suu Kyi's court

The commission was formed at the request of Aung San Suu Kyi, the State Counselor of Myanmar and the country's de facto leader.

Suu Kyi, who won a Nobel Peace Prize for her nonviolent campaign against the military junta that ruled the country for decades, came to power after her party won a landslide victory in the country's 2015 elections, though the military still wields a significant amount of power.

International humanitarian groups have so far expressed disappointment in Suu Kyi's response to the situation, alleging that she has not done enough to stymie the unrest and protect the Rohingya population.

Suu Kyi has denied some of the more severe allegations made by rights organizations, including that ethnic cleansing is occurring in the region.

"Rather than deal with ongoing atrocities, the government tried to hide behind the Advisory Commission," said Matthew Smith, the CEO of human rights group Fortify Rights. "The Commission responded with concrete recommendations to end violations, and the government should act on them without delay."

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Outside observers are also concerned that authorities could ignore some of the report's findings in favor of a similar inquiry by the Myanmar government, which Human Rights Watch called "inept."

Robertson says now that the commission's findings are now public, "the ball is now in Suu Kyi's court."

"We want to see a firm agreement to implement these recommendations, to say very clearly what's going to be done," he said. "The statement so far has been, we'll implement what we can depending on the situation on the ground. You couldn't get more vague than that."