Thiruvananthapuram/New Delhi: Kerala Chief Minister Pinarayi Vijayan on Sunday termed as "unfortunate" and "serious" the blast at a convention centre of a Christian religious group in Kalamassery in Kochi in the morning.

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.

Speaking to reporters in Delhi, Vijayan said he has conferred with the State DGP who along with other senior police officers have left for the blast site.

"It is an unfortunate incident. One person died and two others are in serious condition. An investigation has been launched and further details will be available later," the CM told reporters in Delhi where he has gone to attend some party programmes.

"The incident is being viewed very seriously," he added.

One person died and over 20 were injured were injured in the blast. PTI