As many as ten localities infour cities in Gujarat have been placed under cluster quarantine to contain the spread of coronavirus after some attendees of the Tablighi Jamaat event in Delhi last month tested positive in these areas, a senior official said on Monday.These comprise six localities in Ahmedabad, two in Vadodara and one each in Surat as well as Bhavnagar, said Ashwani Kumar, Secretary to Chief Minister Vijay Rupani."When members of Tablighi Jamaat returned to Gujarat from Delhi, it led to spread of COVID-19 cases. Because of this, six areas in Ahmedabad, that is one in Bapunagar, two in Kalupur, and one each in Dariyapur, Shah Alam and Danilimda, were converted into cluster quarantine," Kumar said.Similar is the case with Nagarwada and Saiyadpura in Vadodara, Sachin in Surat and Sandhiyawad in Bhavnagar, Kumar added."Such a step has been taken to ensure the spread of coronavirus is contained in areas where these Tablighi Jamaat attendees have tested positive," he said.A health department official on Monday said at least 10 of the 16 new COVID-19 positive cases detected had a link to the Tablighi Jamaat event in Nizamuddin.Cluster containment strategy is meant to contain the disease within a defined geographic area by early detection of cases, breaking the chain of transmission and thus preventing its spread to new areas, as per health ministry guidelines.A containment zone is decided on the basis of extent of cases listed by surveillance teams.Agiven geographical area is quarantined, put under enhanced active surveillance, and measures taken comprise testing of all suspect cases, enforcing strict perimeter control for social distancing measures, said an official.