The Indian Army retaliated, triggering heavy exchanges, they said.
In Rajouri, the administration sounded alert and advised the residents to stay indoors in the wake of the Pakistani shelling, Deputy Commissioner Shahid Iqbal Choudhary said.
The Pakistani action affected a population of 4,500-5,000 in villages of Panjgrain, Rajdhani and Naika in Rajouri-Poonch belt, he added.
"The Pakistan Army initiated unprovoked firing on Indian Army posts in Rajouri sector and Poonch district around 0730 hours (7.30 am). The Indian Army retaliated strongly and effectively," a Defence spokesman said.
In the exchange of fire, Naik Muddasar Ahmed was grievously injured when mortar shells landed on his bunker, the spokesman said, adding that he succumbed to his injuries later.
The 37-year-old jawan is survived by wife Shaheena Muddasar and two children.
"Ahmed was a brave and sincere soldier. He loved his job to the core," the spokesman said, adding "The nation will always remain indebted to him for the supreme sacrifice and devotion to duty."
The Pakistani troops also targeted civilian areas in Balakote, Manjakote and Baroti belts of Rajouri, a police officer said.
In the firing and shelling, 9-year-old Sajada Houser was killed at Baroti, the officer said.
"Heavy mortal shelling was reported in forward areas of Tehsil Manjakote in Rajouri this morning. A population of 4,500-5,000 in villages of Panjgrain, Rajdhani and Naika among others was affected," Choudhary said.
Two civilians were injured in the shelling, he said, adding one seriously injured Shah Begum was admitted in district hospital while other injured Sharief Ahmed was given first aid.
"District Administration ordered closure of all schools early morning. However, 120 students were held up in Government School at Panjgrain and on report of headmaster, senior officers coordinated for their safe evacuation as shelling was reported of have affected nearby area," the DC said.
"The firing and shelling exchanges stopped at 1445 hours (2.45 pm)," the defence spokesman said.
Later in the day, Pakistani troops resorted to unprovoked firing at three villages in Kamalkote area of Uri in Baramulla district at around 3 pm, defence sources said.
They said one soldier was injured in the firing.
Intermittent firing by Pakistani troops was going on till last reports came in.
In this month, seven people, including four jawans, have died in firing and shelling by the Pakistani Army along the LoC in Jammu and Kashmir.
Image: Naik Muddasar Ahmed, 37, belonged to the village of Duchoo.
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