Arpit Nishad (16) was killed while his two brothers Luvkuch (15) and Dheeraj (21) were injured when the mud wall of their house collapsed due to rains in Behda village of Kerakat area, police said.
The injured were admitted to a hospital where they are undergoing treatment, it said.
According to Met department, Lucknow received 13 cms of rainfall, Mirzapur, Dudhi, Robertsganj 8 cms each, Ghorawal, Varanasi 7 cms each, Churk 6 cms, Jaunpur, Sitapur, Varanasi 5 cms each, Meja, Koroan, Chunar, Rajghat 4 cms each, Soroan, Karchana, Phoolpur, Ramsanehighat, Aligarh, Bijnore, Mahroni 3 cms each.
The department said rain or thundershowers would occur at many places in east UP tomorrow.