“It’s difficult to say. At this moment, every organization is suspect. Until we have strong evidence, it is difficult to point finger at any organization,” the home minister told reporters.

He was asked about an email attributed to the Pakistan-based Harkat-ul-Jehadi Islami (HuJI) and if investigators were pursuing any cross-border link to the terror attack that killed 13 people, mostly litigants, outside the court complex and injured over 90.

“Whether this one has been carried out by an Indian module or a cross-border module, I cannot say," the minister said. He reiterated his statement in parliament following a debate on terrorism last month.

“There are so many modules. As a part of reality, we have to wake up to that reality. There are Indian modules. Because there is no evidence of HuJi’s presence in India; therefore we are keeping our fingers crossed until we get evidence,” he said.

He said the emails attributed to HuJI and the home grown terror group Indian Mujahideen were being verified. The HuJI email was traced to a cyber cafe in Jammu and Kashmir's Kishtwar and the police there have detained the sender, identified as Mohammed Saeed.

Chidambaram said the government was doing “its best” to improve counter-terrorism infrastructure. “We have reached a modest level in two years and eight months (since the Nov 26, 2008 terror attack and after he took over). It will take time to build capacity to a level where we can say we are perhaps equal to the challenge,” he said.