MOSCOW, Russia (AP) — Security forces killed dozens of protesters and 12 police died during extraordinarily violent demonstrations in Kazakhstan that saw government buildings stormed and set ablaze, authorities said Thursday. One police officer was found beheaded in escalating unrest that poses a growing challenge to authoritarian rule in the Central Asian nation.

Despite the severe response by authorities, protesters took the streets again in the country’s largest city, Almaty, a day after breaking into the presidential residence and the mayor’s office there. Police were out in force again, including in the capital of Nur-Sultan, which was reportedly quiet, and Russian troops were on their way.

Russia’s Sputnik news service reported that shots were fired as police surrounded one group of about 200 protesters in the city. So far, 2,000 people have been arrested, the Interior Ministry said.

In the unrest on Wednesday, “dozens of attackers were liquidated”, police spokeswoman Saltanat Azirbek told state news channel Khabar-24, using a term common to describe the killing of people thought to be extremists by law enforcement. Twelve police officers were killed in the unrest and 353 injured, according to city officials cited by the channel.

Tens of thousands of people, some reportedly carrying clubs and shields, have taken to the streets in recent days in the worst protests the country has seen since gaining independence from the Soviet Union three decades ago. Although the demonstrations began over a near-doubling of prices for a type of vehicle fuel, their size and rapid spread suggest they reflect wider discontent in the country that has been under the rule of the same party since independence.