Police say four people have died in an explosion that collapsed a building in the English city of Leicester. Officials said Monday another four people are hospitalized and more people may be missing. A search and rescue operation is continuing. Superintendent Shane O'Neill of Leicestershire Police says the building where the incident happened consisted of a shop and a two-story apartment above it. The building collapsed after the explosion and was engulfed in flames. Police declared a major incident and evacuated neighbors as a precaution. The cause has not yet been established. Police say it does not appear to be related to terrorism. Leicester is 110 miles (180 kilometers) north of London.