COPENHAGEN — The inventor Peter Madsen is accused by the Danish authorities of binding and abusing the journalist Kim Wall on board his submarine before killing her, according to an indictment released in full on Tuesday.

Mr. Madsen has given shifting explanations for what happened to Ms. Wall, 30, a prolific Swedish journalist who disappeared after boarding the vessel on Aug. 10 in Copenhagen to interview him, and whose torso was found on a beach south of the city on Aug. 21.

Most recently, he admitted to dismembering her body, but he said that she had died in an accident.

In the indictment, however, prosecutors say he brought a “saw, sharpened screwdrivers, straps, strips and pipes” to the submarine before the trip, arguing that these were part of a plan to kill Ms. Wall. He “abused her by hitting her, stabbed and cut her and he killed her after which he dismembered her body,” the indictment said.

The straps and pipes were tied to her torso and limbs to weight them down after he threw them overboard. The police investigation has not been able to establish the exact cause of death, but say that she was either strangled or had her throat cut.