The mayor's office in Almaty was reportedly set ablaze while more than 200 people were detained as violent protests swept through the country following a gas price hike.
An Instagram live stream by a Kazakh blogger showed a fire blazing in the mayor's office of Kazakhstan's biggest city, and gunshots could be heard nearby.
The building in Almaty on Wednesday was surrounded by protesters who appeared to have broken through security forces' cordons even though the latter deployed stun grenades whose explosions could be heard throughout the city centre.
Police detained more than 200 people as unrest spread across the country, according to the Central Asian country's interior ministry.
The ministry said in a statement that protesters "succumbed to provocations" and "groups of citizens blocked roads and blocked traffic, disrupting public order" during the protests, which saw clashes with security forces that the ministry said left 95 police officers injured.
President Kassym-Jomart Tokayev on Wednesday sacked the Central Asian country's cabinet in a bid to head off unprecedented unrest across the nation.
Tokayev also declared a state of emergency in the capital city of Nur Sultan, his office said.
Tokayev earlier declared an emergency in the city of Almaty and surrounding province, as well as in the western Mangistau province.
An overnight curfew will be in place in from 11:00 PM to 7:00 AM, with restrictions on movement in and out of the areas.
Spike in gas price
The initial cause of the unrest was a spike in prices for LPG in hydrocarbon-rich Mangystau, but a government move to lower the prices in line with protesters' demands failed to calm them.
Reports by independent media suggested that Tokayev's announcement of a new price of 50 tenge (11 US cents) per litre, down from 120 at the beginning of the year, failed to weaken the rallies in Zhanaozen and Mangystau's capital Aktau as demonstrators aired new demands.
Footage from Aktau shared on social media on Tuesday showed thousands of protesters – who had camped in the city centre overnight – encircled by police.
Most had dispersed from the city centre by Wednesday, state broadcaster Khabar reported.
In 2011, at least 14 striking oil workers were killed in Zhanaozen as police crushed a protest over pay and working conditions, the deadliest unrest since the republic gained independence in 1991.
Nazarbayev, who is 81 and had ruled Kazakhstan since 1989, retains control over the country as chairman of the security council and "Leader of the Nation" – a constitutional role that affords him unique policymaking privileges as well as immunity from prosecution.