Denying the Indian allegations that Pak troops had killed two Indian soldiers in a cross-border ceasefire violation, Pakistan on Wednesday called on United Nations Military Observers to investigate the incident.Pakistan’s High Commissioner to India was summoned by New Delhi to protest against Tuesday’s killings, in which India’s chief military spokesman alleged one of the soldiers had been beheaded by Pakistani troops who carried away his head.Pakistan has rejected what it called "baseless and unfounded allegations" but echoed calls of caution from India’s foreign minister by saying both sides need to work hard to maintain a recent rapprochement following peace talks which were revived in 2011, a Foreign office spokesman said here."Pakistan is prepared to hold investigations through the United Nations Military Observer Group for India and Pakistan on the recent ceasefire violations on the Line of Control," the Foreign Ministry said.Meanwhile, Foreign Minister Hina Rabbani Khar told Indian channel CNN-IBN that Islamabad was "a bit appalled at some statements" from India and that she was "saddened"."I represent a government that has invested four years to build normalcy, an environment of trust to move forward to achieve regional peace and internal stability," she said in an interview.Khar said the Pakistani soldier had been "brutally murdered because of Indian firing" but denied that Pakistan operated a policy of "tit for tat"."We are a responsible country, a mature country, we must not all go back to having a go at each other," she told CNN-IBN.She said allegations of ceasefire violations had to be dealt with responsibly and offered to ask the UN military observers to investigate."We can ask a third party to do investigation on this, you know that UN military observers exist, we can call them. We are promising a full inquiry," she said in the TV interview.Her ministry said Pakistan was committed to the 2003 ceasefire and called for existing military mechanisms to be strengthened to guard against future violations."Pakistan is committed to a constructive, sustained and result-oriented process of engagement with India. We have made significant progress. It is important that both sides make serious efforts in maintaining this improvement and avoid negative propaganda," it said.The Pakistani military also denied that its troops were responsible."Indian authorities were informed that Pakistan has carried out ground verification and checked and found nothing of this sort happened as being alleged by India," a military official told reporters.