The United States and Australia have warned of the threat of "imminent" terror attacks in the Indian capital.
The U.S. Embassy issued an advisory that urged tourists to avoid New Delhi's crowded markets, noting that commercial and other areas frequented by Westerners have been targeted in the past.
The Australian Embassy issued a similar advisory.
Indian authorities said they were taking the threats seriously, adding that security in the capital was "adequate."
India is home to a wide range of separatists and insurgents, but Islamist terrorist groups, both homegrown and from across the border in Pakistan, are considered the most dangerous threat.
The last major attack in New Delhi was a series of bomb blasts in busy shopping areas in September 2008 that left 22 people dead and wounded 100 more.
compiled from agency reports