Initially there was a telephonic interview which did not last for more than 10 minutes. I was asked to tell about my professional experience. Then a technical question was asked and before I could get the clarity on the question and answer it, I was told that I could answer it in F2F round and the interviewer concluded the discussion.
After a couple of days I was called for a F2F discussion (I wondered how, as I was not asked or answered any questions in telephonic round). The interview process was very exhaustive. They give you a chunk of their day-to-day task and ask you to do the coding in their office premises. This will take close to 4 hours. During this process of coding itself, a couple of the employees walk in and interview you, asking all sorts of questions which bear no resemblance to your profile or previous work.