American film critic Roger Ebert is recovering in a Chicago, Illinois hospital following an emergency operation. The 64-year-old TV veteran, famed for his 'thumbs up, thumbs down' movie rating system, is in a serious but stable condition in the city's Northwestern Memorial Hospital. Doctors operated on him following reported complications from an earlier procedure to remove a cancerous growth from his salivary gland. His wife CHAZ EBERT says, "Roger is stable and responding well. Roger and I are so grateful for your prayers and support. "Please give the big guy the space and time needed to recover until he is ready to use those thumbs again." Ebert, who won the Pulitzer Prize for criticism in 1975, has undergone four cancer surgeries.