SRINAGAR, India (Reuters) - Pakistan accused India of killing four civilians on the border of the two nuclear powers and India said one of its border guards was killed, heightening tensions before a visit by U.S. President Barack Obama.
India said its forces had killed four Pakistanis planning an attack on Indian soil, although Indian media and opposition parties disputed the official account. The Pakistani army said four civilians had died in Indian shelling.
A senior Indian official with the border security forces said they had retaliated on Monday for machine gun and mortar attacks on about 60 positions strung out along more than 200 kilometres (125 miles) of the border.
"Pakistani rangers fired rocket-propelled grenades in villages near the border and our men have responded," the officer told Reuters.
Monday's incidents, in the Samba district south of Jammu along the international border in Jammu and Kashmir, followed the killing of two Pakistani soldiers by Indian forces on New Year's Eve.
As the hostilities intensified, India's security agencies declared a nationwide alert last week to avoid militant strikes before visits by U.S. Secretary of State John Kerry and President Obama later in January.
Kerry is due to speak at the weekend to an investment summit in Gujarat, at the furthest end of the Pakistani border from Kashmir, the organisers said. Obama will attend India's Republic Day military parade on Jan 26.
Indian media say Kerry will also visit Pakistan, but officials in Islamabad have not confirmed that.
Tensions have risen since Indian Prime Minister Narendra Modi called off peace talks in August. Sporadic rounds of heavy shelling have pounded villages along a previously peaceful stretch of border.
The South Asian rivals, who have fought two wars over Muslim-majority Kashmir, blame each other for an upsurge in firing and shelling that started in October last year.
Last week, the clashes stretched beyond the disputed Himalayan region of Kashmir and touched international waters. Indian Coast Guards said a Pakistani fishing boat laden with explosives blew up in the Arabian Sea.
Pakistani Defence Minister Khawaja Asif on Sunday accused India of pursuing a low-intensity war with unprovoked firing on the international borders.
At least 4,000 Indian villagers have fled their homes since New Year's Eve, officials said, and similar numbers are believed to have fled border areas on the Pakistan side. India closed schools near the border and postponed exams on Monday.
(Reporting by Fayaz Bukhari in Srinagar and Katharine Houreld in Islamabad, Writing by Rupam Jain Nair; Editing by Frank Jack Daniel, Ralph Boulton, Larry King)