Two MS-13 gang members from El Salvador, both in the United States illegally, held three teenage girls against their will and killed one of them in what was described as a satanic ritual, authorities in Houston said Friday.

Miguel Alvarez-Flores, 22, and Diego Hernandez-Rivera, 18, have been arrested and charged with aggravated kidnapping and murder — both first-degree felonies punishable by up to life in prison. Bond has been set at $300,000 for each, but immigration detainers will keep both behind bars.