The blast at a convention centre in Kerala on Sunday that claimed one life and injured 36 others was caused due to an improvised explosive device, state director general of police Shaik Darvesh Saheb said.
The state police chief told reporters in Thiruvananthapuram that according to the preliminary probe the blast occurred due to an IED.
"We are examining it," he said.
"This morning at 9.40 am approximately, there was an explosion in Zamrah International Convention Centre in Kalamassery in which one person died and 36 people are undergoing treatment as per our information," the DGP said.
However, there were conflicting reports about the number of blasts as state ministers VN Vasavan and Antony Raju said there were two blasts, while Congress MP from Ernakulam, Hibi Eden, said there were multiple blasts according to one of his friends who attended the convention.
"What they have told us is that there were two blasts according to the initial findings," the ministers said.
On being asked whether it was a terror attack, the DGP said he cannot say anything at this stage.
"Only after the investigation can I confirm the details. We are examining all the angles. We will find out who is behind this and will take stringent action against them," the top police official said.
He also urged people to maintain peace and remain calm and asked them not to spread provocative or hate messages on social media.
Spreading of provocative or hate messages on social media would invite strict action, he warned.
The DGP also said that as soon as he reaches the blast site, a special investigative team will be constituted.
Meanwhile, Vasavan and Raju told media that many central agencies, including the NIA, were present at the scene.
They also said that the incident occurred at around 9.38 am on the last day of the convention and there were around 2,300 people present there at that time.
The ministers, including state Revenue Minister K Rajan, said that the people were praying with their eyes closed when the blast occurred.
They said that people came from various parts of the state for the convention.
The blasts occurred during the convention of the Jehovah's Witnesses -- a Christian religious group that originated in the United States of America in the 19th century.
According to official figures, one woman died and 36 others were injured in the blast.
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