A young woman, who was kidnapped at gunpoint and taken to a homemade torture chamber rigged with bombs, escaped by diving out of a barbed wire-covered window while handcuffed, police say.

The 26-year-old Israeli woman, who was not named, was taken hostage at gunpoint by an acquaintance, Thomas Fischer, at her flat in Hamburg, northern Germany, on Friday night.

Barbed wire covered the windows of the apartment. Credit:AP

She was handcuffed and then taken to Mr Fischer's flat in Barmbek, a suburb of Hamburg, The Independent reported.

But two hours later, she pushed her way out of a window barricaded with barbed wire, police said.