A 50 year old lady presented with history of pain upper abdomen, nausea, and decreased appetite for 5 days. She had undergone cholecystectomy 2 years back. Her bilirubin was 10 mg/dl, SGOT 900 IU/I SGPT 700 IU/I and serum alkaline phosphatase was 280 IU/I. What is the most likely diagnosis -