Bollywood actress Priyanka Chopra's "Don 2: The Chase Continues" stunt double Bibi, a girl from Berlin, passed away Monday due to unknown reasons. Priyanka, and her co-star, Shah Rukh Khan paid their condolences on Twitter.

"It's shocking how unpredictable life can be. Bibi, my stunt double from Don 2 passed away. Taught me all I did in the film, " Priyanka posted on her Twitter page.

"RIP Bibi... here's a prayer for her and courage her family...from all of us on Don 2, " added the 28-year-old, who is said to have some heavy duty action sequences in the movie.

Shah Rukh, who plays the main lead, wrote: "A prayer from all in Don 2 for our friend & stunt girl Bibi...who left us for a better place. Lov u (sic)."

However, both the actors did't say what was the reason behind Bibi's death.

"Don 2: The Chase Continues", directed by Farhan Akhtar, is the sequel to the 2006 film, "Don: The Chase Begins Again", which itself is a remake of the 1978 film "Don".

The film is set for release in Dec 2011.