Russian-led forces have arrived in Kazakhstan at the request of the country's authoritarian leader, amid a crackdown on anti-government protests.
The interior ministry said 26 "armed criminals" had been "liquidated" and 18 security officers killed in the unrest, sparked by a fuel price hike.
A BBC journalist in the largest city Almaty shared video of heavy gunfire overnight on Thursday.
The UN, US, UK, and France have called on all sides to refrain from violence.
The internet is down, and little independent information is coming through. More than 3,000 people have been arrested, the interior ministry said.
According to local media, 70 checkpoints have been set up across the country.
In a statement on Friday, President Kassym-Jomart Tokayev said "constitutional order [had] largely been restored in all regions of the country" and that "local authorities [were] in control of the situation".
The president. who has blamed foreign-trained "terrorists" for the unrest without giving evidence, said the operations would continue until "the militants are completely eliminated".
As the protests escalated, President Tokayev appealed to the Russian-led Collective Security Treaty Organisation (CSTO) for support. The bloc includes Russia, Kazakhstan, Belarus, Tajikistan and Armenia.
The overseas force reportedly sent about 2,500 soldiers to Kazakhstan. The CSTO says the troops are a peacekeeping force and will protect state and military installations. They will stay in the country for several days or weeks, the Russian RIA news agency reports.
The US state department said it was closely monitoring the deployment of Russian troops. "The United States and, frankly, the world will be watching for any violation of human rights," a spokesman said.
"We will also be watching for any actions that may lay the predicate for the seizure of Kazakh institutions."