Unverified video of the crash showed the plane, which was operated by Azerbaijan Airlines, bursting into flames as it hit the ground and thick black smoke then rising. Bloodied and bruised passengers could be seen stumbling from a piece of the fuselage that had remained intact.
Kazakhstan's emergencies ministry said in a statement that fire services had put out the blaze and that the survivors, including two children, were being treated at a nearby hospital. The bodies of the dead were being recovered.
Azerbaijan Airlines said the Embraer 190 jet, with flight number J2-8243, was flying from Baku to Grozny, capital of Russia's Chechnya region, but had been forced to make an emergency landing around 3 km (1.8 miles) from Aktau in Kazakhstan. The city is on the opposite shore of the Caspian Sea from Azerbaijan and Russia.
Authorities in Kazakhstan said a government commission had been set up to investigate what had happened and its members ordered to fly to the site and ensure that the families of the dead and injured were getting the help they needed.
Kazakhstan would cooperate with Azerbaijan on the investigation, the government said.
Russia's aviation watchdog said in a statement that preliminary information suggested the pilot had decided to make an emergency landing after a bird strike.
Following the crash, Ilham Aliyev, the president of Azerbaijan, was returning home from Russia where he had been due to attend a summit on Wednesday, Russia's RIA news agency reported.
Ramzan Kadyrov, the Kremlin-backed leader of Chechnya, expressed his condolences in a statement and said some of those being treated in hospital were in an extremely serious condition and that he and others would pray for their rapid recovery.
