The tracks of the launch tower of the Soyuz launch pad at the Vostochny spaceport had to be reinstalled due to cavities in concrete, a source in the construction industry told TASS on Thursday.

"The tracks of the launch tower had to be replaced preventatively due to cavities under the Soyuz launch pad. As of now the rails have already been reinstalled," he said.

According to the source, construction workers at the Soyuz launch pad at the Vostochny spaceport are currently drilling boreholes into each cavity that occurred earlier, and pour a special plaster into them.

Russia’s Roscosmos State Space Corporation declined to comment on the information provided by the source.