The Zvezdochka shipyard in northern Russia said on Friday that a recent minor radioactive leak at its storage facility posed no threat to people or environment.

According to a Zvezdochka statement, the "radiation incident" took place on Thursday when about two cubic meters liquid radioactive waste leaked through a seam in a pipe connecting a storage tank and a waste treatment facility.

"The pipe itself is located in a leak-proof tunnel and the waste did not spill outside," the statement said, adding that the tunnel has been drained of the waste in two hours following the leak.

"The radiation levels around the tunnel are normal. The causes of the leak are being investigated," the shipyard said.

Severodvinsk-based Zvezdochka is Russia's biggest shipyard for repairing and dismantling nuclear-powered submarines. It has the capacity to scrap up to four nuclear submarines per year.