AFP news agency investigated into matter and found that the story behind the picture was false. The real story is that the picture is in fact of a mass grave being dug in Pakistan but not in Balakot area. This mass grave was dug in Quetta for victims of a suicide attack in 2013.
https://www.youtube.com/watch?v=eYNHyvskMfk&t=12s
The Hindi-language caption says: “Mass graves are being dug in Pakistan for past 4 days, even then you are stuck on the proof." The post has been shared 700 times.
On February 24, Indian jets intruded Pakistan airspace and dropped payload near Balakot during a hasty escape. India media and authorities claimed that around 350 ‘terrorists’ were killed in the attack, while numerous ‘terrorist hideouts’ were destroyed.
There claims were dismissed by DG ISPR Major General Asif Ghafoor who said that one person was injured while some trees were destroyed. International media outlets such as the BBC also dismissed Indian claims saying that no casualty was reported.
https://www.youtube.com/watch?v=Kc3KAyjMCus
Relations between Pakistan and India are tense ever since the Pulwama Attack, in which 44 Indian paramilitary soldiers were killed in an attack on Indian convoy in occupied-Kashmir.
Also the day after the Balakot Attack, two Indian jets entered Pakistani airspace again but were shot down. Wing Commander Abhinandan was arrested but later released as peace gesture.