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 defense ministry said was caused by a fire that led to the explosion of ammunition.

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 defense 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.