New Delhi: India is closely watching infrastructure development by China in border regions and constantly refining its defence strategy keeping in view the changing security paradigm, Defence Minister AK Antony told Rajya Sabha on Wednesday.

"Government is aware that China is undertaking infrastructure development in the border regions opposite India. Government is closely watching all such developments," Antony said.

"Our defence strategy and doctrines are being constantly refined keeping in view the changing security paradigm," he said in a written reply to a query whether India's military modernization along the Chinese border has run into hurdles.

Noting that the accretion of forces and augmentation of its capabilities is a continuous process, Antony said their deployment is carried out keeping in mind the operational requirements and threat perceptions.

On development of road infrastructure along borders, the Defence Minister said, "73 roads have been identified as strategic border roads, 15 have been completed, 39 are scheduled for completion by 2013 and remaining by 2016."

Replying to another query, Antony denied any input on Chinese and Pakistani army having conducted any joint exercise in the Thar desert.

"There are no inputs of any joint military exercise on the border side of Gujarat and Rajasthan," he told the House.

About analysis and assessment of Chinese naval power, Antony said such an exercise of military capabilities of countries was a continuous process.

"Open domain inputs indicate that construction and deployment of three aircraft carriers (by Chinese Navy), according to strategic and tactical scenarios, is possible in future. Our forces are well prepared for any eventuality," he said, adding that understanding of maritime domain is part of nation's strategic planning.

Replying to a question on infiltration along the India- Pakistan border, he said, "As per the assessment of Multi Agency Centre (MAC), 68 militants attempted to infiltrate across the Line of Control during September and October 2011, as compared to 85 such attempts during the corresponding period in 2010."

12 terrorists were killed and one was apprehended by Army in 2011 while trying to infiltrate in J and K, he said.    "During this period, five army personnel were killed and eight were wounded during conduct of anti-infiltration operations along the LoC," he said.

On the steps taken by the government to check infiltration attempts, he said, "In J and K along the LoC, the Army has adopted a robust counter infiltration strategy which has an appropriate mix of technology and human resources to check infiltration effectively."