More than 100 people were inside at the time . Police tell that the gates were locked when the fire breaks out . Authorities do not know how many people are trapped in the building . The ` ` complicated structure '' and ` ` narrow space '' are posing difficulties for rescuers .
More than 300 workers were inside at the time . Escapees tell Xinhua the gates were locked when the fire breaks out . Authorities do not know how many people are trapped in the plant . The `` complicated structure '' and `` narrow exits '' are posing difficulties for rescuers .