Conway police say people who work in businesses in the industrial park where a chemical exploded yesterday will have to call their employers to see whether their companies are open today. The explosion and fire yesterday at the Detco Industries plant forced thousands of people out as schools and businesses were evacuated. The cause of the explosion is not yet determined. Detco makes industrial chemicals and aerosol products, such as cleaners and disinfectants. State officials say hazardous chemicals were used in production. Emergency workers evacuated everyone within a mile of the plant, on the city`s south side. A Conway police dispatcher this morning said the main intersection near the plant is still closed. Some homes near the plant remain under evacuation and firefighting crews were still spraying water on the remains of the plant.