The officials told news agency Reuters that plots they have uncovered included the kidnapping of foreigners and turning India into a "Syria and Iraq where violence is continuously happening".
"The thing we are looking for is how Al Qaeda/ISIS tie up with local groups, especially as the drawdown takes place in Afghanistan," said Sharad Kumar, head of the NIA (National Investigation Agency), the country's main counter-terrorism arm.
As evidence that militant coordination and activity are on the rise, security officials cite the weekend's suicide attack on the Pakistani side of the border crossing at Wagah, and a terror alert on Tuesday at the Kolkata post that forced the navy to withdraw two ships.

Allegiances between Islamist militant groups can be murky and fleeting, and providing concrete proof of operational ties is notoriously difficult.
But Indian security agencies said evidence they have gathered points to growing ties between Al Qaeda and the IM, a home-grown movement which has used relatively crude weapons like pressure cooker bombs but executed several major terror attacks in the last few years.
"The thing we are looking for is how Al Qaeda/ISIS tie up with local groups, especially as the drawdown takes place in Afghanistan," said Sharad Kumar, head of the NIA (National Investigation Agency), the country's main counter-terrorism arm.
As evidence that militant coordination and activity are on the rise, security officials cite the weekend's suicide attack on the Pakistani side of the border crossing at Wagah, and a terror alert on Tuesday at the Kolkata post that forced the navy to withdraw two ships.
Allegiances between Islamist militant groups can be murky and fleeting, and providing concrete proof of operational ties is notoriously difficult.
But Indian security agencies said evidence they have gathered points to growing ties between Al Qaeda and the IM, a home-grown movement which has used relatively crude weapons like pressure cooker bombs but executed several major terror attacks in the last few years.