The leader of Indian-administered Kashmir has ordered a massive manhunt after 24 Hindus were shot dead by suspected militants.
Bodies of the victims are laid out
Police said unidentified gunmen shot members of the state's minority Hindu community - many of them women and children - near the southern town of Shopian.
It is the worst such attack since a new government was elected in Indian-administered Kashmir last September.
Many people had hoped the vote, which was largely peaceful, would ease tensions in the region over the disputed state.
Chief Minister Mufti Mohammad Sayeed described it as an act of frustration.
"The enemy within and across the border is committing such inhuman and senseless acts out of frustration to derail the peace process."
Senior Indian cabinet ministers held an emergency meeting to review the situation after which they decided to send Deputy Premier LK Advani to Kashmir.
Pakistan has condemned the attack, calling it "a blatant act of terrorism".
The American Ambassador in India Robert Blackwill also condemned the attack.
He said the United States looked "forward to the terrorists being brought
swiftly to justice."
Late night raid
The Kashmir director-general of police, AK Suri, said gunmen dressed in army uniforms
entered Nadimarg village near Shopian - about 50 kilometres (30 miles) south of the summer capital Srinagar.
They told police they were Indian army soldiers and wanted to carry out a search operation.
They then snatched the policemen's weapons and shot their victims.
Eleven men, 11 women and two children were among the victims.
Nadimarg is usually guarded by eight police officers, but only four were on duty on Sunday night when the attack took place, an officer told the AFP news agency.
Correspondents say the killings will be a major setback for Kashmir Chief Minister Mufti Mohammed Sayeed, who has appealed to Kashmiri Hindus to return to the disputed state.
Neighbours of the victims grieve
Hundreds of thousands of Hindus have fled since separatist violence broke out in the state in 1989.
Mr Sayeed's election was seen as a landmark after he unseated the party that had ruled Kashmir since Indian independence.
The BBC's Jill McGivering in Delhi says the latest attack is another blow to an administration which had promised to restore normality in the troubled state with what they described as a "healing touch".
But the state has witnessed a sharp rise in violence in the past few weeks after months of relative peace.
On Sunday, a leading separatist leader, Abdul Majid Dar, was shot dead by suspected Islamic militants.
Mr Dar was a former member of the Hizbul Mujahideen - one of the main militant groups fighting Indian rule in Kashmir - but was expelled from the group last year.
Tens of thousands of people have died in the struggle against Indian rule in Jammu and Kashmir, India's only Muslim-majority state.