The actor's daughter, Mercedes, told the reputable newspaper The New York Times that the cause of her father's death was pneumonia.
The Hollywood star's heir also reported that Val was diagnosed with throat cancer in 2014, but the disease soon retreated.
Many acquaintances of the actor commented on his death, including director Michael Mann, who directed the legendary "Heat" (1995) with Kilmer in the role of crew member Chris Shiherlis:
Actor Josh Brolin, known for "Deadpool 2," wrote on his Instagram that he would miss Kilmer. Josh called Val a "smart, cheeky, bold, incredibly creative firecracker."Chris ShiherlisI have always admired his versatility, his brilliant adaptability within the powerful flow that Val possessed and expressed. This is extremely sad news.

Source:
imdb.com
As stated in the biography of the late artist, his creative journey began in the 1980s and includes a whole gallery of unforgettable characters: from pilot Iceman in "Top Gun" (1986) to the legendary rock musician Jim Morrison in the biographical drama "The Doors" (1991).
Kilmer is remembered by audiences not only as Batman in the film "Batman Forever" (1995) but also as King Philip in the historical drama "Alexander" (2004).
Over the years, the actor worked with some of the greatest directors of modern times, including Oliver Stone and Francis Ford Coppola. Despite having a reputation as a difficult actor to work with, many colleagues, including Robert Downey Jr., spoke of him as a dedicated professional with a unique creative vision.
Kilmer was never afraid to experiment with roles, refused predictable characters, and sought to play "unusual people in extreme circumstances."
According to IMDb, the actor appeared in over a hundred films, many of which became truly iconic. For some, he will be remembered as the best Batman, for others as the perfect embodiment of Jim Morrison on screen, and for others as a versatile actor for whom there were no impossible roles. Earlier, we at zoomboola.com reported on the death of actress Émilie Dequenne, who passed away at the age of 43.