<span style="color: #222222;">Defence Minister Rajnath Singh says the gap between internal and external security is getting narrower. However, new dimensions of security threats are emerging. He said threats of cyber and information warfare pose a big challenge to the security architecture.<br />''<br />''Speaking at the convocation ceremony of the National Defence College in Delhi today, Mr. Singh said, the critical infrastructure, such as power generation, transport, public sector and critical manufacturing industries are vulnerable to cyber-attacks.<br />''<br />''On the challenge of information warfare, the Defence Minister said it has potential to threaten the country's political stability.<br />''<br />''He said organised use of social media and other online content generation platforms is being used for engineering the opinion or perspective of the masses.</span><br />