This reminds me about Samsung galaxy note7 explosion, A redmi note4 handset is exploded in Bangalore. According to the video posted in social media, A shopkeeper who was inserting simcard in customers handset, Suddenly flames came out. The handset is neither connected to charger or any other device, It exploded in bare hands and the shopkeeper is absolutely fine.
Redmi company responded to this event and they replaced the mobile with a new piece and stated that,
“customers safety is our priority and we will investigate on this issue”
This is the rare case happen because the mobile is not in charging mode or it is in heat mode, Officials we’re investigating on this and they will give more details then by,
Let’s hope these explosions stop and don’t degrade the companies reputation.