A 40 year old male, with history of daily alcohol consumption for the last 7 years, is brought to the hospital emergency room with acute onsent of seeing snakes all around him in the room, not recognizing family members, violent behavior and tremulousness for few hours. There is history of his having missed the alcohol drink since 2 days. Examination reveals increased blood pressure, tremors, increased psychomotor activity, fearful affect, hallucinatory behaviour, disorientation, impaired judgment and insight. He is most likely to be suffering from: