PUNE : At least 12 trainee sailors of the Lonavala-based INS Shivaji, one of the premier training establishments of the Indian Navy, have so far tested positive for coronavirus, officials said.The first case was found on June 18 and the infected cadet was part of a batch of 157 trainee sailors who had reported back after leave following the easing of lockdown earlier this month, a release issued by the naval station on Tuesday said."With the easing of lockdown as per Unlock 1.0 in the first week of June, a batch of 157 trainee sailors who were undergoing training at this establishment and were on extended leave in view of the lockdown, reported back and all were quarantined for 14 days in one of the institutional quarantine facilities.