A 39-year-old South Africa returnee was retested on Monday and turned out to be positive for Covid-19, the Chandigarh administration said.
One of his family members and domestic help were also tested positive for the virus.
As per protocol, the positive cases are being shifted to an institutional quarantine facility.
The samples of the positive cases will be sent for whole genome sequencing to the NCDC, Delhi, to ascertain the variant or variant of concern, if any, an official statement said.
"A 39-year-old male resident of Sector 36 had returned from South Africa on November 21. He was RT-PCR negative on his arrival at the airport. He was quarantined at home on his arrival in Chandigarh," it added.