Six states are looking for people who attended the event and might have contracted coronavirus.
Ground information to electronic media - the police from at least nine states have been using all methods to navigate the contact tracing nightmare that has come up after the people who attended a massive religious gathering at Delhi's Nizamuddin area started testing positive for the highly contagious coronavirus. Seven people have died, one in Jammu and Kashmir and six in Telangana.
Now a hunt is on across Uttar Pradesh, Madhya Pradesh, Andhra Pradesh, Telangana, Jammu and Kashmir, Rajasthan, Assam and even faraway Andamans. Total positive cases are now close to 100 -- 24 cases have been detected in Delhi, six in Telangana, 10 in Andamans, 50 in Tamil Nadu, four in Andhra Pradesh and one in Jammu and Kashmir. The overall figure is 96.
Close to 2,000 people had been staying at "Markaz Nizamuddin", the Delhi headquarters of the Muslim religious organisation Tablighi Jamaat, which had organized the event. Among the attendees were a number of people from COVID-positive nations.
On March 28, the home ministry wrote to state governments, saying it "received information that foreign delegates of Tabligh Jamaat -- the religious organization holding the event -- are on tour of Indian hinterland and are believed to be carriers of COVID-19". The ministry had asked the police from all states to locate, screen and quarantine them.
Sources said the ministry has given high priority to contact tracing from the gathering - which has now been marked a "hotspot" of the virus. Home Minister Amit Shah is being briefed about the situation every day.
Tamil Nadu, which showed the highest number of positives, has been chasing more than 1100 people who attended the gathering and those in contact with them. Andhra Pradesh, which had an equally long list, has already traced 711 people, 194 have been traced in Telangana.
The greater success in Andhra Pradesh is owing to the use of electronic means - the state police have been relying on an app to track COVID-positive patients.
The app - developed by the state police - can also monitor those under home quarantine and can detect any movement 30-50 metres from home. Of the 28,000 people under surveillance in Andhra Pradesh, around 25,000 are already on the app, which was launched last week.
Besides, the police are also using information from cellphone towers to track patients. Besides more than 2 lakh people from villages are also supplying groud information to the authorities.
In Uttar Pradesh, relying on ground information, the police traced eight preachers of Tablighi Jamaat at a mosque in Nagina. All eight came from Indonesia.
"They came to Delhi via Bangladesh and then went to Odisha, On March 21, they reached the Jamunwali masjid in Bijnore's Nagina," said Sanjay Singh, a senior police officer from Bijnor.
In Jammu and Kashmir, where contact tracing would otherwise have been a nightmare, a lot of people are coming forward with information, the police said.
The second Coronavirus-positive patient who died in Jammu and Kashmir had attended the Delhi event. In Kashmir, he had come in contact with a number of people, said the police, who are now gathering information on how many people from the new Union Territory had attended the event.
So far, they have tracked down more than 100 people who have come in contact with Tablighi Jamaat members who attended the mosque congregation in Delhi.
Officials say aggressive contact tracing is done to control the spread
of virus.
Under hashtag #Togetherweshallfight, senior Jammu and Kashmir official Rohit Kansal tweeted: "Aggressive contact tracing of positive cases key to control spread of Coronavirus. Yesterday several areas surrounding location of positive cases or untraced contact cases had to be sealed in Jammu, Srinagar, Pulwama, Shopian, Rajouri."