India is likely to blacklist about 300 foreigners who came from 16 countries on tourist visas but attended an Islamic congregation at Nizamuddin here that has become a key source for the spread of Coronavirus in the country, officials said on Tuesday.

These foreigners were among around 8,000 people who attended the Tabligh-e-Jamaat at Nizamuddin Markaz facility in March, many of whom have shown symptoms of COVID-19, a Union Home Ministry official said.