David Lagercrantz has another two Millennium novels in the pipeline, his Swedish publisher said Wednesday, two months after his first sequel to Stieg Larsson's best-selling crime trilogy hit the shelves.

In a statement from his publishing house Norstedts, the author of "The Girl in the Spider's Web" said: "I can't let it go. It was such fun to write and an incredible adventure. Furthermore, I think I have a very good story going."

The Millennium series, which chronicles the adventures of tattooed computer hacker Lisbeth Salander and journalist Mikael Blomkvist, made Larsson one of the world's best-loved crime writers.

But the fame came posthumously, after his death of a heart attack in 2004, a year before the release of the first book in the series, "The Girl With the Dragon Tattoo".

That book was followed by two others, which together sold over 80 million copies worldwide.

Lagercrantz's first sequel, "The Girl in the Spider's Web", which was released in 25 countries on August 27, picks up the trail of the intrepid hacker-hack duo.

So far, 2.7 million copies have been printed.

The Guardian's reviewer called it "a respectful and affectionate homage" but The New York Times concluded "the sublime madness of Larsson's original isn't quite there."

The fifth book is scheduled for release in 2017, with the sixth following two years later, Norstedts said.

While many Larsson fans rejoiced over the continuation of the series, some -- including his longtime partner, Eva Gabrielsson -- vehemently opposed Lagercrantz taking up the torch.

Previously best known for his biography of footballer Zlatan Ibrahimovic, the writer told AFP in August he was "scared to death" his work would not live up to Larsson's legacy.