The United States warned India before last week's brutal attacks in Mumbai that terrorists appeared to be plotting a mostly waterborne assault on its financial capital, a senior Bush administration official said Tuesday. The official would not elaborate on the timing or details of the US warning to Indian counterparts. The official confirmed, though, that Washington passed on information it had about a possible attacks, speaking on condition of anonymity because of the sensitive nature of intelligence information. The revelation of US involvement comes as the Indian government faces widespread accusations of security and intelligence failures after the attacks last week. Suspected Muslim terrorists carried out a three-day assault that killed 172 people and wounded 239 in the heart of Mumbai. US Secretary of State Condoleezza Rice is set to visit India Wednesday, carrying the US demand that Pakistan cooperate fully in the investigation into the attacks and to try to reduce tensions between India and Pakistan, who share a long and deadly rivalry.