While seven people were killed in Rohtas district, five each died in state capital Patna and Kaimur districts.
According to officials, three people died each in Saran, Kaimur, Saharsa and Katihar; two people each in Bhojpur, Samastipur, Bhagalpur, Munger and Madhepura, and one each in west Champaran and Gaya districts.
Lightning strikes during the monsoon season (June until second half of October) are common in Bihar.
The monsoon arrived in Bihar on June 17 in the north-eastern parts and on Tuesday it entered Patna, Gaya, Aurangabad and the rest of the state.
The toll is expected to rise as reports from the remote areas are yet to reach the state capital.
Disaster Management Principal Secretary Vyas Jee has asked the District Magistrates to send reports about the extent of damage in their districts due to the lightning. Patna’s Met department also warned of heavy rains with more lightning in some parts of Bihar in the next 48 hours.
"We got the information on Tuesday that several people were killed due to lightening. The latest information says that 46 people are dead, eight are injured and two are critically injured. An eight feet pit has been created due to the lightning. I request all not to stay in open areas," Vyas told ANI.
Bihar Chief Minister Nitish Kumar has announced an ex-gratia of four lakh rupees to the kin of those killed in the incident.
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