The warehouse at the center of a massive explosion in northeastern China this week was storing hazardous chemicals closer to residential areas than allowed by safety regulations, spurring angry calls for authorities to investigate.

At least 85 people were killed and more than 700 injured after the explosions late Wednesday ripped through the dockside facility in Tianjin, a major port city. Local authorities said the warehouse housed hazardous goods, although investigators Friday said they still hadn’t determined the types...