'Harry Potter' Actor Paul Ritter Dies of Brain Tumor at 54

Paul Ritter -- best known around the globe for playing Eldred Worple in "Harry Potter and the Half-Blood Prince" -- has died.

A rep for the British actor says Paul died of a brain tumor Monday night. He died peacefully at home with his wife Polly and sons -- Frank and Noah -- by his side. The rep added, "He was fiercely intelligent, kind and very funny. We will miss him greatly. Paul was an exceptionally talented actor playing an enormous variety of roles on stage and screen with extraordinary skill."

Some of Paul's bigger credits include appearing in the James Bond movie "Quantum of Solace" as government adviser Guy Haines. In his homeland ... Paul was best known for playing the family patriarch in the long-running Channel 4 comedy "Friday Night Dinner."

He was also a brilliant stage actor that landed him both Olivier and Tony Award nominations. Paul's work in "Coram Boy" earned him an Olivier nomination in 2006. His starring role in "The Norman Conquests" in 2009 snagged him a Tony nomination.

He was most recently in the HBO miniseries "Chernobyl" ... portraying Anatoly Dyatlov, the supervisor who was blamed for not following safety protocols leading to the nuclear disaster.

Paul was also set to appear in the upcoming World War II drama "Operation Mincemeat."