The number of COVID-19 cases inGoa reached 15 late Saturday night after two passengers who had alighted from a Delhi-Thiruvananthapuram train at Madgaon near here tested positive for novel coronavirus, a health official said.Out of the 323 passengers on the train, samples of 129 were tested and reports of two returned positive and their samples have been sent to Goa Medical College and Hospital virology lab for confirmation, he said."Rest of the samples from the train will be tested tonight. All passengers who alighted at Madgaon station have been taken to district hospital for testing. They will be quarantined at JN Stadium."Of the other five cases detected here today, two came from West Bengal, and the others from Haridwar, Mumbai and Ratnagiri," he said.