According to reports, the warning comes after LTTE militants were spotted near Navi Mumbai.
Earlier, the Intelligence Bureau after intercepting a phone call from Pakistan Occupied Kashmir (PoK) had issued a terror alert across metro cities in India on Nov 2.
A terror alert was issued in Bangalore, New Delhi, Mumbai and Ahmedabad following which the security was beefed up.
On the same day, news of bomb scare were doing the rounds at the Karnataka High Court.
Following the triple blasts that took place in Mumbai on Jul 13, 2011, IB had issued terror alerts across the nation of possible terror attacks through sea.
After the Delhi high court blast that took place outside the Gate number 5 at 10.17 am on Sept 7, a nation wide alert was issued by the Home Ministry.
A month after on Oct 12, 2011 the Ambala police foiled a terror bid in course of routine operation after they found a car laden with explosives, timer devices, detonator and RDX.
Later, it was found that the haul of explosives that was recovered from a car outside the Ambala Cantonment Railway Station was meant to avenge the 1984 anti-Sikh riots and kill the accused Congress leader, Sajjan Kumar.
Reports revealed that the actual plan was to target Kumar when he appeared for a court hearing in the the Karkardooma Court, East Delhi on Oct 19 in connection with the 1984 Sikh riots case by the Khalistan Tiger Force (KTF).
The KTF also claimed in the press release that they will keep trying to kill Sajjan Kumar till they succeed.
This is the second such warning from the IB this month, with the first coming on Nov 2.