Jammu, Feb 5: Four Indian soldiers, including a 22-year-old officer, were killed and four other persons were injured on Sunday in Pakistani firing on the Line of Control (LoC) in Jammu and Kashmir's Rajouri and Poonch districts, Army officials said. Indian Army also said that "heavy damage" was inflicted on Pakistan Army posts in retaliatory action. A statement said Pakistan Army initiated "unprovoked" and "indiscriminate" firing around 3.30 p.m. in Bhimber Gali sector in Rajouri. "Indian Army retaliated strongly and effectively and heavy damage has been inflicted on Pakistani Army posts," said a defence statement. "However, in the exchange of fire, one officer and three jawans were grievously injured and succumbed to their injuries..." The killed soldiers include Captain Kapil Kundu, who would have celebrated his 23rd birthday on February 10. Hailing from Haryana's Gurugram, he is survived by his mother Sunita. The others were Riflemen Ramavatar, 27 from Baraka village in Madhya Pradesh's Gwalior, Subham Singh, 23 from Jammu and Kashmir's Kathua, and Havilder Roshan Lal, 43 of Jammu and Kashmir's Samba. "Martyrdom of Indian Army soldiers will not go in vain. The unprovoked action by Pakistani Army will be given a befitting response," the statement added. Earlier on Sunday, a 15-year old girl and a soldier were injured in Pakistan ceasefire violation in Shahpur area of the LoC in Poonch district. According to army officials, the firing started around 11 a.m. with Pakistani soldiers using small arms, automatics and mortars. Indian troops retaliated strongly, they added.