Military men at a guard station in Zolote town in Lugansk in eastern Ukraine on February 11, 2019. Photo: AFP/TTXVN

A car exploded in the parking lot near the headquarters of the local government building and residents of Donetsk were asked to "remain calm, be vigilant and avoid moving about the city."

Reuters quoted a source of Russia's Interfax as saying that a gas pipeline in the self-proclaimed Luhansk People's Republic also exploded and caught fire on Friday evening. However, it is not clear whether the incident caused any casualties.

The incidents took place as people in both Donetsk and Luhansk had been told to evacuate to avoid possible dangers.

The situation along the contact line in the Donbass region in eastern Ukraine took a turn for the worse on Thursday morning. Observers from the Organization for Security and Cooperation in Europe (OSCE) reported 80 times violating the ceasefire with some of the most intensive shelling in recent months. The Ukrainian authorities and militias in Donbass accused each other of the shelling.