Mumbai's domestic and international airports were put on high alert after receiving a terror threat on late Monday night. Security has also been strengthened at the city's famous Taj Hotel, which was one of the locations attacked by Pakistani terrorists in November 2008.
The police said the airport manager on duty late on Monday night had received a phone call warning that there could be bomb blasts at the airports and the Taj Hotel.
The caller reportedly said he had overheard a plan to attack the three locations with explosives packed in vehicles.
Sources said the police suspect it was a hoax call, but are taking no chances. It has been described as a "specific threat" and there is massive security and a bomb squad each deployed at all three locations. A source in the Mumbai Police said that the three locations are already high-security zones with special forces guarding them.
The threat comes a day before 12 men convicted for the 2006 serial train blasts in Mumbai are sentenced on Wednesday.
The hotel was one of the prominent targets of the 26 / 11 terror attacks in which 166 people were killed in 2008.