A massive fire broke out onSaturday evening at a slum beside railway tracks in south Kolkata's Selimpore area, partially affecting train services, officials said.Ten fire tenders were rushed to douse the blaze that broke out around 8.30 pm near Dhakuria railway station, they said.No casualty has been reported, fire brigade officials said, adding that the cause is yet to be ascertained."The fire is massive and it has spread from one shanty to another. Initially, five fire tenders were working but that could not control the blaze that spread to an adjacent apartment. At the moment 10 fire engines are working in tandem," a senior official said.Train services in the Sealdah south section have been affected due to the fire, a senior official of the Eastern Railway said.Services on both up and down lines that connect Sealdah to Diamond Harbour, Canning and Sonarpur have been temporarily suspended as a precautionary measure, he added.