John Leeson, the actor best known for providing the voice of the robotic dog K9 in the long-running British science fiction series "Doctor Who," has died at the age of 83. Born John Ducker, he passed away after a period of illness, according to a statement posted by his son, Guy Ducker, on social media. Guy described his father's passing as peaceful.

Leeson's career spanned several decades and included a variety of roles across British television. Beyond "Doctor Who," he appeared in series such as "Dad’s Army," "Sorry!," and "Longitude." His television work also encompassed appearances on "The Bill," "Vanity Fair," and "Blake’s 7."

Russell T Davies, who served as showrunner for "Doctor Who," paid tribute to Leeson on Instagram, highlighting his contribution as the voice behind the beloved character K9. Davies also noted that Leeson had returned to voice K9 in 2006 during the revival of the series.

Leeson’s portrayal of K9, the loyal robot dog companion to the Doctor, left a lasting impression on fans of the franchise, cementing his place in the show's history. His work has been recognized and remembered by colleagues and viewers alike following his death.