A rupture in an old natural gas pipe has emerged as the most likely cause of Friday's blast in the Lithuania-Latvia pipeline, the head of its operator said on Saturday.
The explosion yielded flames up to 50 meters high, but there was no immediate evidence of an attack.
"The initial survey showed that a welding seam simply tore open", Nemunas Biknius, head of Lithuania's gas transmission operator Amber Grid, told BNS wire.
Police opened an investigation on Saturday into whether the pipeline was properly maintained but is not currently investigating whether it was damaged intentionally, BNS said.
The fire emanating from the more than 40-year old pipeline was put out on Friday but a highway next to the blast site remains closed.
Several dozen people evacuated from a nearby village have all returned to their homes, the head of the local public administration Povilas Balciunas told Reuters.
(Reporting by Janis Laizans in Pasvalys and Andrius Sytas in Vilnius; Editing by David Holmes)