NUR-SULTAN: Kazakhstan's president said Tuesday a criminal investigation has been opened into a munitions depot blast that killed two people and left 165 injured in a town in the south of the country.

Authorities evacuated Arys, a town of 40,000 people, following Monday's blast which the defence ministry said was caused by a fire which caused ammunition to explode.

Social media users shared videos of residents fleeing the area, where properties were damaged, as huge plumes of smoke rose in the background.

Kazakhstan's Prime Minister Askar Mamin said Tuesday during a government meeting that "one civilian and one serviceman" were killed and 165 people had sought treatment.

Newly-elected President Kassym-Jomart Tokayev Tuesday visited the injured at a hospital in Shymkent, a city close to Arys.

He said in a tweet he had ordered the interior and defence ministries to prevent further explosions and pledged perpetrators would be "prosecuted under the law."

"A criminal case has been opened".

He pledged the government would restore the town and compensate victims.

Regional governor Umirzak Shukeyev said Arys had been almost completely evacuated Monday but warned explosions at the depot might continue for several days.

Three people were arrested for looting in Arys, Interior Minister Erlan Turgumbayev said.

The disaster was an important test for Tokayev 66, who was elected in a June 9 vote that international observers criticized as showing "scant respect" for democracy.

He is a loyal ally of long-time leader Nursultan Nazarbayev, 78, who shocked Kazakhs by stepping down from the presidency in March but who is still expected to call the shots in the oil-rich Central Asian country of 18 million people.

Munitions depot blasts are not uncommon in Central Asia, where many depots are holdovers from Soviet times.

Monday's blast was the fourth time the depot near Arys has been a site of explosions, with three people killed during a blast in 2009. —AFP