"This is one more in a series of provocations and barbaric actions by the enemies of peace," Singh said in a statement in Frankfurt en route to the United States to attend the United Nations General Assembly session on the sidelines of which he will meet his Pakistani counterpart Nawaz Sharif on Sunday for talks.
"We are firmly resolved to combat and defeat the terrorist menace that continues to receive encouragement and reinforcement from across the border," he said.
In a twin terror attack, three heavily-armed militants dressed in army fatigues on Thursday stormed a police station and an army camp in Jammu region killing 12 people including a Lt Colonel and six other security personnel.
"No words are strong enough to condemn the heinous terrorist attack on Hira Nagar police station and Army camp at Sambha in Jammu and Kashmir this morning," Singh said.
"Such attacks will not deter us and will not succeed in derailing our efforts to find a resolution to all problems through a process of dialogue," he said, indicating that the talks with Sharif will go ahead as per schedule.
"I convey my heartfelt condolences to the families of the brave army and police officers as well as the innocent civilian martyred in this cowardly attack," he added.
Bilateral relations soured after five Indian soldiers were killed by Pakistani troops along the Line of Control last month.
New Delhi has also been urging Islamabad to take steps to stop terrorism emanating from Pakistani soil and to prosecute those responsible for the 2008 Mumbai attacks.
Image: Prime Minister Manmohan Singh arrives at Frankfurt on his way to New York, on Thursday
Photograph Courtesy: PMO
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