The state conducted testing on 3,485 samples in the last 24 hours registering an infection rate of 6.85 per cent, he said.
At least 34 people have succumbed to the infection so far and the number of active cases now stands at 2,861.
As many as 8,487 people have recovered from the infection.
Of the 239 fresh cases, Aizawl district reported the highest cases at 149, followed by Lawngtlai and Lunglei district, which reported 35 and 21 cases respectively, the official said.
The remaining cases were reported from Kolasib, Siaha, Saitual, Khawzawl, Serchhip, Champhai and Mamit districts, he said.
Fifty cases were confirmed at an RT-PCR laboratory in Zoram Medical College (ZMC), while 178 cases were detected through Rapid Antigen Test and the remaining 11 were detected through TrueNat tests, he said.
Five frontline workers (all ambulance drivers), a BSF jawan and over 46 children were among the newly infected people, according to the official.
Three patients have travel history and the rest 236 were found to be locally contracted the virus, he said.
Of the 236 locally infected patients, 150 were diagnosed with COVID-19 during contact tracing and it is to ascertain how the remaining 86 patients contracted the virus, he added.
Meanwhile, 195 people were discharged from various COVID-19 Care Centres on Thursday.
The Northeastern state has so far tested 3,81,291 samples for COVID-19 and 2.99 per cent of them came out positive for Covid-19.
The recovery rate is 74.57 per cent.
According to state immunization officer Dr Lalzawmi, 2,51,894 people have been administered the first dose of COVID-19 vaccine of which 52,052 people have received both the doses till Thursday.