This comes from Clanbase and TTLG, both of whom cite the same Russian language interview with studio president Sergey Grigorovitch.

The expansion is subtitled “Call of Pripyat” and is due out later this year. While S.T.A.L.K.E.R. 2 was mentioned, no details were given.

The post-apocalyptic first-person shooter/RPG was released back in 2007, with “Clear Sky”, the expansion prequel, out the next year.