NEW DELHI - Ties between India and Pakistan took a turn for the worse with New Delhi abruptly putting off a scheme to give visas on arrival to Pakistani senior citizens, and as Prime Minister Manmohan Singh warned it could not be "business as usual" between the two countries.
"What has happened is unacceptable," Mr Singh told reporters, referring to the killings of two Indian soldiers, which India has blamed on Pakistan. One of the soldiers was beheaded.
"Those responsible for this crime will have to be brought to book," Mr Singh said on a day when the Pakistani government itself was plunged into political crisis.
Tensions between India and Pakistan have been escalating since Jan 8 following the killing of the two Indian soldiers and constant firing across the Line of Control, the de facto border between the two countries.
Pakistan has denied it was behind the killings and in turn said that two of its soldiers were killed by Indian fire on the Line of Control.
The escalating tension, the worst in nine years, raises questions on the future of ongoing peace talks between the two countries.
There was a clear hardening of the Indian government's position on Tuesday in the face of growing public anger. It also came a day after some tough talking from Indian Army chief General Bikram Singh who threatened to retaliate against Pakistan for the killing of two soldiers.
On Tuesday New Delhi put off the implementation of a scheme to give visas on arrival for senior citizens above the age 65 in one fallout of the border tension.
The Indian counter at the Wagah border was suddenly shut at 2:30 pm Indian time with the home ministry saying there were some last minute "technical issues" that needed to be sorted out.
That was part of a wider easing of restrictive travel conditions between the two countries. Under the new scheme, for instance, people with visas travelling between the two countries can visit up to five cities instead of the earlier three.
The visa liberalisation scheme, signed in September last year, was hyped as an important confidence building measure between the two countries, a bid to forge a new relationship based on easier movement of goods and people across borders.
External Affairs Minister Mr Salman Khurshid in a press conference was clear that India could not ignore what it saw as a "lack of response" from the Pakistani side over the two soldiers' killings.
India had lodged a diplomatic protest and asked Pakistan to investigate the killings.
"It should not be felt that the brazen denial and lack of proper response from the government of Pakistan... will be ignored and that bilateral relations would be unaffected... Such actions by the Pakistani Army which are in contravention of all norms of international conduct not only constitute a grave provocation but lead us to draw appropriate conclusion about Pakistan's seriousness in pursuing normalisation of relations with India," Mr Khurshid said.
Sporting ties between the two countries also took a hit over the escalating border crisis with Hockey India, a sporting body, deciding to send back all nine Pakistani hockey players who were supposed to play in league matches.
"After discussion with all the stakeholders, the Hockey India and Pakistan Hockey Federation have mutually decided to send them (Pakistan players) back due to an extra-ordinary situation which has arisen," Hockey India secretary general Narinder Batra told reporters in reference to the tension along the border. He also said that it was for the security of the Pakistani players.
The far right group Shiv Sena has been protesting the presence of Pakistani players in the teams.
Mr Khurshid was clear that India would do everything it could to push for action but refused to give details.
"We are extremely determined and serious in this concern of ours and we have taken resort to all such instruments and methods available to us at this time," he said.