Vietnamese court sentenced four men to death for dealing in heroin, adding to those waiting capital punishment while the government tries to source chemicals for lethal injection, state media reported Thursday. The country has not executed anyone since 2011, when it decided to switch from firing squads to lethal injections on humanitarian grounds. But it has found itself unable to get chemicals used in the injections because of an EU ban on its factories exporting drugs used in lethal injections. The state-run Laborer newspaper said the four were convicted on Wednesday in northern Vietnam for dealing in 50 kilograms of heroin. Vietnam has some of the world’s toughest drug laws. Trafficking or trading 600 grams of heroin is punishable by death. There are currently more than 500 people on death row.