The Kremlin on Thursday cautioned against "hypotheses" over the crash of an Azerbaijani plane which had been due to land in Russia as experts pointed to possible evidence of a missile explosion.

The Azerbaijan Airlines jet crashed near the Kazakh city of Aktau, an oil and gas hub, on Wednesday.

Thirty-eight of the 67 people on board died.

"It would be wrong to make any hypotheses before the investigation's conclusions," Kremlin spokesman Dmitry Peskov told reporters.

The Embraer 190 aircraft was supposed to fly northwest from the Azerbaijani capital Baku to the city of Grozny in Chechnya in southern Russia, but instead diverted far off course across the Caspian Sea.

An investigation is underway, but some aviation and military experts said the plane may have been accidentally shot by Russian air defence systems as it was flying in an area where Ukrainian drone activity had been reported.

Russian military expert Yury Podolyaka said holes seen in the wreckage of the plane were similar to the damage caused by an "anti-aircraft missile system".

"Everything points to that," he wrote.

A former expert at France's BEA air accident investigation agency, also said there appeared to be "a lot of shrapnel" damage on the wreckage.

Speaking on condition of anonymity, he said the damage was "reminiscent" of Malaysia Airlines flight MH17, which was downed with a surface-to-air missile by Russia-backed rebels over eastern Ukraine in 2014.

But Kazakh Senate speaker Maulen Ashimbayev condemned "speculation" about what happened.

He said it was "not possible" to say what may have damaged the plane, he was quoted by Russian news agency TASS as saying.

Azerbaijan Airlines initially said the plane flew through a flock of birds before withdrawing the statement.

The airline said there were 62 passengers and five crew members on board.

Kazakh officials said 38 people had been killed and there were 29 survivors, including three children.

Jalil Aliyev, the father of flight attendant Hokume Aliyeva, told AFP that this was supposed to have been her last flight before starting a job as a lawyer for the airline.

"Why did her young life have to end so tragically?" the man said in a trembling voice before hanging up the phone.

Eleven of the injured are in intensive care, the Kazakh health ministry said.

Azerbaijan state news agency Azertac reported that 12 of the survivors were being flown to Azerbaijan.

A plane carrying nine injured Russian nationals, including a child, also arrived at Zhukovsky airport in the Moscow region on Thursday, Russia's emergency situations ministry said.

Day of mourning

Azerbaijani President Ilham Aliyev declared Thursday a day of mourning and cancelled a planned visit to Russia for an informal summit of the Commonwealth of Independent States (CIS), a grouping of former Soviet nations.

Aliyev's office said the president "ordered the prompt initiation of urgent measures to investigate the causes of the disaster".

"I extend my condolences to the families of those who lost their lives in the crash... and wish a speedy recovery to the injured," Aliyev said in a social media post on Wednesday.

The Flight Radar website showed the plane deviating from its normal route, crossing the Caspian Sea and then circling over the area where it eventually crashed near Aktau, an oil and gas hub on the eastern shore of the sea.

Azerbaijan Airlines said the plane "made an emergency landing" around three kilometres (1.9 miles) from Aktau.

Kazakhstan said the plane was carrying 37 Azerbaijani passengers, six Kazakhs, three Kyrgyz and 16 Russians.

Bloodied survivors

A Kazakh woman told the local branch of Radio Free Europe/Radio Liberty (RFE/RL) she was near where the plane crashed and rushed to the site to help survivors.

"They were covered in blood. They were crying. They were calling for help," said the woman, who gave her name as Elmira.

She said they saved some teenagers.

"I'll never forget their look, full of pain and despair," said Elmira. "A girl pleaded: 'Save my mother, my mother is back there'."

Russian President Vladimir Putin held a phone conversation with Aliyev and "expressed his condolences in connection with the crash", his spokesman Dmitry Peskov told a news conference.

A Russian emergency situations ministry plane was sent to Aktau on Wednesday with medical personnel and other equipment.

Chinese President Xi Jinping also called his Azerbaijani, Kazakh and Russian counterparts to send his "deep condolences", according to CCTV.

The French foreign ministry also sent condolences and said it hoped for "a swift recovery for survivors".

AFP

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