Did Cinna die in Catching fuego o did the peacekeepers just badly injure him?

He's dead

Yes, Peace keepers came in and beat him and in the movie it appears he may have died, but in the libros it is assumed that he was beaten than killed during interrogation .

In Mockingjay, Katniss is told that Cinna is believed to have been killed during interrogation.

I haven't read the book yet, but this is what I've worked out from how I've seen others reply to similar questions: he wasn't killed immediately just before Katniss entered the arena for the 75th Games. Then he was just badly beaten up. However, he was imprisoned, interrogated and later killed. I don't think he reappears before his death.

Cinna is dead it says so in mocking arrendajo, jay and its obvious in the movie that he's dead

they killed him ;(