Three Russian nationals, an Iranian citizen and four locals have been caught in an explosion that rocked downtown Yerevan, Armenia late on Monday. The blast occurred at a fast-food restaurant and was caused by a faulty pressurized gas canister, according to preliminary findings. An investigation into the incident has been launched. Police have already ruled out any malicious intent. All the victims have been hospitalized, and the three Russian teenagers have sustained not life-threatening injuries, namely bruises and fractures, according to a representative of the Armenian emergency services.