Rescuers search for four missing after three killed in chocolate factory blast

Rescuers are continuing the search for four people missing after an explosion at a chocolate factory in Pennsylvania which killed three people (Ben Hasty /Reading Eagle/AP)

Rescuers are continuing the search for four people missing after an explosion at a chocolate factory in Pennsylvania which killed three people.

Crews using dogs and imaging equipment continued to scour the rubble after the blast that happened just before 5pm on Friday at the RM Palmer plant in the borough of West Reading, about 60 miles (96km) north-west of Philadelphia.