At least 26 persons were killed on Saturday when a water boiler blew up in a factory in the Bangladeshi capital Dhaka, police said. Many others were in critical condition.The explosion led to a huge fire in the Tampaco Foils factory in Gazipur area around 6 a.m., bdnews24 reported, citing Senior Fire Station officer Mohd Rafiquzzaman.Fire Service Headquarters Director Lt Col Mosharraf Hussain said 25 units battled the flames, which caused two floors of the five-storey building to partially collapse.An official told Dhaka Tribune that 10-15 persons may still be trapped inside the building.Seventeen bodies were sent to Tongi Hospital and three to the Dhaka Medical College and Hospital, the Daily Star reported. A total of 74 others were injured, many critically, police said.In a condolence message, Prime Minister Sheikh Hasina, expressed deep shock at the deaths and injuries.Director of Labour (Joint Secretary) SM Ashrafuzzaman told reporters that families of the deceased workers would get Taka 2 lakh each and the injured a maximum Taka 1 lakh each as grants from the labour welfare fund.A five-member probe body has been formed to look into the incident.