Accusing Pakistan of not making any serious attempt to dismantle terror infrastructure, India on Wednesday said that this was a cause for 'major worry' and it will examine 'all the available, possible options'.

Sending a tough message a day after Prime Minister Manmohan Singh [Images] spoke of the involvement of Pakistan's state agencies in the Mumbai [Images] terror attack, Defence Minister A K Antony said, "We will do everything to prevent such attacks".

"There is no serious attempt to dismantle terror outfits working across the border. This is our major worry," Antony told reporters.

"We will examine all the available, possible options," he said without elaborating.

The minister expressed New Delhi's [Images] apprehensions of stepped-up infiltration from across the borders in Jammu and Kashmir [Images] in the summer months.

"Even in winters, militants have infiltrated into Jammu and Kashmir. It is biting cold now. Militants will step up infiltration into J& K from now. Summers will see heightened infiltration. So armed forces should remain vigilant," he said.

Stating that it was Pakistan's duty to book those people, who supported terrorists during the Mumbai attacks on November 26 last year, the defence minister said the neighbour should also dismantle the over 30 terror outfits working from its soil.

"To prevent the repetition of infiltration and terror incidents, two things needed to be done. Those people, who gave support to terrorists in the 26/11 attack in Mumbai, should be booked. The over 30 terror outfits working from across the border should be dismantled. It is Pakistan's duty," he said.