Local authorities have closed traffic and evacuated some nearby households after the crack appeared on the morning of August 2.
Gia Nghia City People's Committee Chairman Do Tan Suong said that they've urgently moved 16 households from the area after their houses also saw cracks.
"We're investigating the incident to have a proper solution," Suong said.
Earlier on Tuesday, a huge crack of over 200 metres in length also appeared in Tuy Duc District, 80 kilometres from Gia Nghia City following a loud explosion caused by some minor quakes. The crack has expanded to over a kilometre now while hundreds of residents have been evacuated.
Dozens of households in the central highlands province of Dak Nong have been isolated by serious flooding and landslides triggered by heavy rains following Storm Doksuri.
Two hydropower plants in Gia Nghia City, the Dak R’Tih and Dak Nong 2, also faced landslides in some areas. The Dak Nong 2 plant had to temporarily suspend operation for repair work.
