Bulgaria is investigating the cause of an explosion at a weapons storage facility, including the possibility of sabotage and a link to a previous blaze at another site operated by the same company, EMCO ▻ ↧ Explosion hits another EMCO weapons site in Bulgaria; probe underway Bulgaria is investigating the cause of a fire at a weapons storage facility ‌operated by EMCO, including the possibility of sabotage and a link to a previous blaze at another of the company's facilities in August, the interior minister said.