Peter Madsen claimed in court testimony that he buried journalist Kim Wall at sea after she was accidentally killed on his submarine, according to reports

Inventor Alleges Journalist Was Accidentally Killed on His Submarine Before He Dumped Her Body at Sea: Reports

Danish submarine inventor Peter Madsen claimed in court testimony on Tuesday that he buried Swedish journalist Kim Wall at sea last month after she was killed in an accident on his privately-built underwater vessel, according to multiple reports.

The 46-year-old Madsen described his version of the events surrounding Wall’s death during an hours-long court hearing in Copenhagen, Denmark, according to the Guardian, the New York Times and Reuters.

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After that proceeding, Madsen was ordered held for four more weeks and the charge against him was upgraded from involuntary manslaughter to manslaughter, the Danish legal equivalent of murder, according to these reports.

Wall’s torso — armless, headless and legless — was found on the Copenhagen shore days after she vanished, police said on Aug. 22. The next day, they said they had positively identified her body. Her cause of death has not been publicly disclosed.

Madsen denies being responsible for Wall’s death. PEOPLE has been unable to reach his attorney for comment. He is reportedly due in court again on Oct. 3.

In court on Tuesday, Madsen testified that Wall, a 30-year-old freelance journalist, had joined him on his submarine on Aug. 10 while working on a story.

In his testimony, Madsen claimed that while they were out in the water that night, after the submarine returned to the surface, he climbed through the hatch and was holding it open for Wall to follow him through when he lost hold of it and it struck her in the head, causing her to fall to the submarine’s floor.

The hatch weighed about 150 lbs. and was slippery, he testified. After she was allegedly hit, he went back down to check her pulse but she didn’t have one, he said in court.

“It was a terrible accident, a disaster, no doctor could have done anything,” Madsen said. “Kim was severely injured. There was a pool of blood where she landed.”

Madsen’s testimony was not embraced, as the judge at his hearing described his claims as “not reasonable,” according to the Times.

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Image zoom Peter Madsen Niels Hougaard /Ritzau. File/AP

Image zoom Kim Wall TOM WALL/EPA

“In my shock I thought it was the right thing to do,” he said of performing “a funeral at sea” for Wall.

“I didn’t want a dead body in my submarine,” he said. “I put a rope around her feet to drag her out.”

Madsen testified that he used nylon strap to secure pieces of iron pipe to Wall’s body before dumping it overboard. He said he also considered killing himself.

On the morning of Aug. 11, he testified, he saw rescuers approach his submarine so he opened a valve to let in water — intentionally sinking the vessel — and then jumped out to swim to safety.

During Tuesday’s court appearance, Madsen was asked during his testimony to provide an explanation for Wall’s severed head and limbs. “She was in one piece,” he claimed of the last time he saw her.

Local authorities are continuing their search for the rest of Wall’s remains.

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Police say Madsen has given a shifting account of Wall’s final hours, including initially claiming he had returned her — alive — to land after their outing. He later told investigators she died accidentally while aboard the submarine.

Asked in court on Tuesday about these changing statements, Madsen said, according to the Times:

“I wanted to see my wife and the three cats. I wanted to see them before all this was going to happen. I had no doubt that everything would come to light. I just wanted five minutes to say goodbye to my wife.”