This is the third travel alert issued by the United States.
"The US Government continues to receive information that terrorist groups may be planning attacks in India," the travel alert statement said.
"Terrorists and their sympathisers have demonstrated their willingness and capability to attack targets where Americans or Westerners are known to congregate or visit," it said.
According to media reports, intelligence agencies indicated that suicide bombers have entered India with the objective of creating Mumbai-type mayhem.
"In addition, there continues to be a possibility of violence in the south-central Indian state of Andhra Pradesh over the contentious issue of creating a separate state," the State Department said.
The US said there is also the possibility of violence in Andhra Pradesh as civil unrest continues over the contentious issue of statehood for the Telangana region.
Protesters have targeted public transportation, attacking trains and burning numerous buses. Public transport networks have been forced to shut down several times," the State Department said.