What just happened?

As the loud sounds went off ,Kai quickly woke up from his apartment complex to the shock of his life as his windows were completely smashed and blood stains were on the streets below him along with bodies ranging from children to adults

Kai hurriedly got his apartment keys and quickly grabbed his phone and switched it on but to no avail... then he used his apartment keys and unlocked his doors and went round his neighbors doors to get a briefing of the situation but then he heard a sound..... TO BE CONTINUED