At least four people have been killed and another 25 injured after a freight train derailed and exploded in northeastern Bulgaria. <br /><br /> The incident took place in the small town of Hitrino. <br /><br /> Many victims are reportedly being treated in hospital for burns after two of the train’s tanks, which contained flammable chemicals, blew up after hitting electricity cables. <br /><br /> Authorities have ordered an evacuation while 150 firefighters tackle the massive blaze. <br /><br /> 20 buildings are said to have been seriously damaged following the incident.<br />
