Mushtak Ahmed of RAJUK's architecture department tested positive for the coronavirus infection on Monday.
RAJUK's chairman and few other officials have since quarantined themselves at home, according to its Director Sharmin Jahan.
“Those of us who worked with them on Sunday have been asked to remain careful, and we’re currently in isolation,” Sharmin told bdnews24.com on Tuesday.
Mushtak, however, said he hadn't ventured out of his home since the lockdown was imposed, although a friend had visited him the day before Eid-ul-Fitr.
He later came to know that his friend was diagnosed with COVID-19 and went for a test on Sunday.
“I am asymptomatic and not suffering from any health problems. But I’m staying at home as I've tested positive. I went to the office for two days but didn't come into contact with others.”
Bangladesh has reported 52,445 cases of COVID-19 until Tuesday with 709 fatalities, including former RAJUK Chairman M Bazlur Rashid Chowdhury.