It's just awful, Eddie the article has some minor inaccuracies or is not very complete.
The tragic event has taken place at an 'albergue', sort of like a rural, very basic hostel, I guess. A man had thrown a party to celebrate his 50th. B-day, there were 50 guests, thirty of which, because there were big carnival festivities in the nearby town of Vinaroz, decided to go party instead and probably saved their lives that way. From the 20 that stayed, the host and his partner slept in another room because the rest insisted they had a more private and intimate night....and they saved their lives for certain! They were also the ones that discovered the bodies of their 18 dead friends the next morning!
All the 5 members of the band hired to perform during the shinding have died, including a 19-year-old.
It's yet to be said if the gas heaters that burnt badly were provided by the 'albergue' or the guests brough them themselves....
At least they had a peaceful death.