Eighteen people were killed and several others injured since Sunday as heavy rainfall accompained by thunderstorms lashed the state, official sources said in Lucknow on Monday.
Six persons died in Duaba area in Ballia district after being struck by lightning.
Also, four others in Chandauli, four in Sonebhadra, two in Rae Bareli and two in Mirzapur died due to lightning and falling of trees at various places in these districts.
In Sultanpur, Hardoi and Faizabad, a number of trees were uprooted and houses were damaged following thunderstorm and heavy rains.
Communication systems were also affected with seepage of water in underground telecom cables, officials said.
The rains, however gave some relief to people from the sweltering heat prevailing in the state.