JOIN USFrancisco Javier Dominguez, 19, who had been taken to Zacamil Hospital in San Salvador, died from "cardiorespiratory arrest", officials at the medical center told EFE.
The convict suffered "multiple organ failure" as a consequence of second- and third-degree burns over 40 percent of his body, an official said.
Elsewhere, spokespersons at Rosales Hospital said that three inmates remain in that medical center, one of whom has shown a "slight improvement", though his condition is "delicate", while the others are "improving with a good prognosis".
The blaze broke out last Wednesday in Section 1 of the youth prison in Ilobasco, a town located some 55 km northeast of San Salvador.
Flames swept through an area that housed 43 of the 96 convicts in Ilobasco prison, which holds inmates over the age of 18 serving time for crimes committed when they were minors and who cannot be sent to serve the rest of their sentences in the adult penitentiary system.
Originally 16 prisoners died in the fire and 22 were hurt, but in recent days 10 of those who were injured and taken to hospital have also died.The authorities still have not issued a report on the causes of the incident.