Researchers at the University of Barcelona, one of Spain's most prestigious universities, had detected the presence of the novel coronavirus in wastewater samples collected here on March 12, 2019, the university said in a statement on Friday.

Axar.az reports citing foreign media that the study was led by researchers from the Enteric Virus Laboratory of the University of Barcelona in collaboration with the public-private company Aigues de Barcelona, which is responsible for managing the water cycle in Barcelona's metropolitan area, it said.

"These results, sent to a high impact journal and published in the archive medRxiv, suggest the infection was present before knowing about any case of COVID-19 in any part of the world," the statement said.

The study "has not been peer-reviewed," the researchers said on medRxiv, an online archive distributing unpublished health sciences documents.