With dozens dead after protests over hikes in fuel prices escalated into full-blown fighting, the people of Almaty were struggling to come to terms with the Central Asian country's worst crisis in years.

Protesters had stormed and set alight government buildings including the mayor's office and a presidential residence, which was gutted and still smouldering when AFP correspondents entered on Thursday.

Saule, a 58-year-old construction worker who took part in the protests, said she was stunned when security forces opened fire on demonstrators.

"We saw the deaths," she said. "Straight away about 10 were killed."

Overnight, social media was inundated with videos of machinegun fire and people screaming in fear as authorities launched what they called "anti-terrorist" operations.

By the afternoon on Thursday, the official death toll stood at 13 security officers -- including two who were allegedly decapitated -- and "dozens" of protesters.

People were walking around in a daze at the presidential residence Thursday afternoon, taking pictures and shooting videos of splatterings of blood and discarded bullets scattered across the leafy complex.

"I didn't know that our people could be so terrifying," said Samal, a 29-year-old nursery school teacher.

Anger at corruption

Energy-rich Kazakhstan was long seen as one of the most stable of the ex-Soviet republics of Central Asia.

The country was ruled with an iron fist since 1989 by Nursultan Nazarbayev, who in 2019 stepped away but appointed a loyalist successor in President Kassym-Jomart Tokayev.

Tokayev promised reforms, but the country saw little change and remained staunchly authoritarian, with Nazarbayev still seen as in charge behind the scenes.

Discontent was bubbling beneath the surface, protesters told AFP, and in recent days chants of "Old Man Out!" -- in reference to the 81-year-old -- echoed across Almaty.

Critics see Nazarbayev as having fostered rampant corruption, enriching himself and his family who boast lavish residences abroad.

"Our Kazakhstan has been turned into a private company of the Nazarbayevs," Saule said, adding that protesters had only wanted to "overthrow corruption".

Authorities have moved to snuff out the violence, detaining around 2,000 people in Almaty and inviting Russia-led troops for a peacekeeping mission.

They have also instituted a nationwide state of emergency that restricts movements, bans mass gatherings and imposes an overnight curfew.

On Thursday, people milled about on the square opposite the mayor's office but large crowds were absent.

Still, AFP correspondents heard sporadic bursts of gunfire as fighting appeared to continue.

'Pseudo-freedom' gone

On a main artery through Almaty, smoke billowed out of offices housing several media outlets, and AFP correspondents spotted several burned-out cars.

Shops had been looted, including a hunting store that passersby said was ransacked by protesters seeking weapons to battle government troops.

In a gutter on one street, AFP correspondents saw empty boxes with markings that indicated they had been used to store ammunition.

Several streets were closed with checkpoints.

For some Almaty residents, the fear was that a harsher version of authoritarianism could now descend on the country.

"We had a kind of pseudo-freedom," said Sultan, 29, who did not participate in the protests. "We could go about our daily lives."

"Now even that has gone. It is the fault of the system the authorities chose."