"They are going after the very soul of South Asia, the very heart of the Pakistani people," Assistant Secretary of State for South and Central Asian Affairs Richard Boucher told reporters in Washington.
His remarks came when he was asked to comment on Tuesday's attack on the Sri Lankan cricketers in Lahore that left seven players and an assistant coach injured and eight people dead.
He said these attacks are something which is a cause of concern. "We would watch for the Pakistani authorities to investigate and find out who did it," Boucher said.
So far neither the Pakistan Government nor the Sri Lankan authorities have approached the United States for help in their investigations. However, the US is always ready to offer all its assistance, if requested for, he said.
Boucher spoke with Sri Lankan Foreign Minister Rohitta Bogollagama on Friday and extended the Obama Administration's condolences over the attack on the cricketers.
When asked if there is any link between the attack on the Sri Lankan cricketers in Lahore and the LTTE, Boucher said "the basic answer is, I do not known."
"I do not know of any link like that at this point, but what we need to do is to let the Pakistani authorities do the investigation. I think they have said that they have some leads and some people in custody. So we look to see what they say about this," he said.
Asked if he had reasons to believe that LTTE or Al-Qaeda had any links in the past, Boucher said: "I do not know anything about that."
"Frankly, God knows", he said when asked what these terrorists are trying to achieve.
"I do not have any idea. Right around the same time (of Lahore attack), there was an attack on a Sufi shrine in Peshawar. Attack on a Sufi shrine, cricket team, I mean who are these people? What they are trying to do, it is not just to disrupt modern school or things like that?" he asked.
"They are going after, the very soul of South Asia, the very heart of the Pakistani people. So all of us understand very clearly that terrorists are a real threat to any aspiration that the people of Pakistan have to living a normal life, living a modern life. I do not have a clue why somebody would attack people like these," Boucher said.