Security agencies were on Wednesday examining CCTV footage at the site of the blast at a Ganga ghat here which left a child dead and 37 injured even as a forensic team from Agra collected samples from the spot.
A day after the blast took place between the Dashashwamedh and Shitla ghats which was teeming with devotees during the time of Ganga 'arti', police barricaded the site of the explosion and devotees were not allowed to take a dip in the river.
The main entrance to the Shitla temple has been closed.
At other ghats, the number of visitors has reduced considerably, the police said. The BJP has called for a bandh and shops were closed but normal life in the city was unaffected.
ADM (city) Atal Kumar Rai said authorities are examining CCTV videos recorded at the site of the incident. He said if people have come across any video footage or evidence regarding yesterday's blast, they should immediately give it to the authorities.
Rai said a forensic team has come from Agra and has collected samples from the site of the explosion. Sources said the team has found metals splinters even as the police carried out extensive checking of hotels examining their records relating to visitors.
Meanwhile, out of the 37 injured in the blast, one is said to be in a critical condition.
In Mumbai, a father-son duo were picked up for questioning in connection with the e-mail sent by banned terror group Indian Mujahideen to several media houses claiming responsibility for the Varanasi blast.
The terror mail was traced to a residential complex in Navi Mumbai. The five-page email sent by Indian Mujahideen has been sent using an unsecured WiFi of Airtel Broadband of the two, official sources said.
The two were questioned and later released, they said. Mumbai police commissioner Sanjeev Dayal told PTI that the email has been traced to Navi Mumbai and the police of that area and Mumbai Police were coordinating to trace the culprits.
Meanwhile, Uttar Pradesh chief minister Mayawati visited Varanasi to take stock of the situation.
"On the basis of a report sent by senior officials, the chief minister reached Varanasi, visited both the ghats, took stock of the situation and inquired about the investigations and injured," they said.
Mayawati said the injured would be given free treatment at Lucknow besides financial assistance.