According to the spokesman, suspicious objects were found near the blast area that could be pieces from an explosive, although he did not rule out other explanations.
"Experts are investigating the cause of the incident, but there is the possibility it was due to a break in the sealing," he said.
The incident occurred at 2:30 a.m. local time on Monday [GMT 22:30 on Sunday]. Gas deliveries have been renewed to the city of Khasavyurt.
There were no reports of injuries.
In a separate incident in the capital of the volatile North Caucasus republic, Makhachkala, a police officer was wounded when unidentified assailants fired automatic weapons at the security booth of a hotel, shattering the window.
"Unidentified assailants hidden in [nearby waste ground] shot at the hotel's security booth using automatic weapons," a spokesman said.
A 25-year-old sergeant received first aid at the scene.
