So did Hikaru get burned while trying to save Hajime or did he set himself on fire?

Hikaru attempt suicide, but failed
While hajime most likely killed himself or set himself on fire after killing his mother (i think hajime already have depression) (i also think that hajime try double suicide with his mother since there is "MURDE-SUICI" in paper)

Yeah, I figured out that Hajime killed his mom and then himself by fire given the news articles and the scene at the beach. Hajime already having depression makes sense. Also. I initially thought Hikaru looked burned in the hospital so I was confused but maybe the injuries are from jumping off the building.