A son of a U.S. soldier stationed in South Korea has died after taking a psychoactive drug with alcohol, police here said Thursday. According to the Yongsan Police Station, the 21-year-old son, whose identity is being withheld, died in an apartment in Yongsan-gu, central Seoul, on Feb. 20 after taking the psychotropic drug containing alprazolam. An autopsy showed he died from taking a massive amount of the prescription medication while he was heavily intoxicated with alcohol, officers said. Alprazolam can be prescribed to treat panic and anxiety disorders. Despite the fact that abusing the powerful drug can lead to death, it\'s not uncommon for people to mix the drug and alcohol to achieve a high.    After an analysis of CCTV footage taken at the scene, police said they have confirmed there were others, including his girlfriend, who is also the child of another U.S. soldier. \"A complete examination has not come out yet, but there is a high possibility that they also took the drug,\" a police officer leading the investigation said. \"They are not (U.S.) soldiers, but the Korea-U.S. Status of Forces Agreement (SOFA) applies to them, meaning that we will request custody of them if deemed necessary,\" the officer added. The SOFA governs the legal status of U.S. troops stationed in the country. About 28,500 U.S. troops are stationed in South Korea as part of the two allies\' defense against North Korea.