The accused has been identified as Kasim Sheikh, a resident of Meethapur and native of West Bengal, they said.
Police received information on Tuesday at around 12:30 a.m. regarding the incident. After reaching the spot, a person was found lying on the floor of a room. He was taken to a nearby hospital where he was declared brought dead, a senior police officer said.
The deceased was later identified as Vinod Yadav, a resident of Farrukhabad in Uttar Pradesh.
Investigation revealed that Yadav had a relationship with the wife of Sheikh which he got to know. Sheikh was living in a shanty at the same plot whereas Yadav used to live in a rented accommodation.
"In the intervening night of Monday and Tuesday, Sheikh hit Vinod on his head with an iron rod due to which he died on the spot," said Chinmoy Biswal, Deputy Commissioner of Police (Southeast).
A case under section 302 (punishment for murder) of the Indian Penal Code has been registered at Jaitpur police station, the DCP said.
"Sheikh was arrested and the iron rod used in the crime has been recovered. Yadav was a contractor for shuttering in house construction, while Sheikh used to work as a rag-picker and car cleaner," said Biswal.
( With inputs from IANS )