How did Prim die and why?

She was one of the medics that got into the center of the fight in the Capitol. She was blown up along with others, but it seemed that it was Gale and Coins doing.

She died when she got blown up in the capitol. Gale and Beete were the ones who invented the bomb, so technically it is there fault.

Okay so prim was put as one of the medics that was attending to the capital children in front of snows mansion when the rest of the parachutes went off killing the rest of the children and the medics that was there.
Her dyeing was because of coin since Katniss if the face of the rebellion she can make one déplacer and turn everyone against coin if she really wanted that’s why coin put Prim on the front line because she knew if anything were to happen to her Katniss would never be able to cope with it, so she killed her trying to break Katniss but only creating a plus rise of hatred toward President Coin.