The crime was committed on November 11 and the accused has been arrested.
The victim, Shilpi, lived with her husband, Ajay, and their four-year-old son in Noida's Chijarsi village.
According to the police, Shilpi was in an extramarital relationship for three years with another man, Pradeep.
Pradeep wanted Shilpi to leave her family and live with him. He was constantly pressuring her to do so, the police told the media.
On Nov 11, Pradeep went to see Shilpi at her house after her husband left for work.
He again pressed her to leave her husband and son, to which she refused. This led to a heated argument, during which, Pradeep strangled Shilpi to death.
During their fight, Shilpi's son, who was asleep in the next room, woke up and witnessed the murder of his mother.
During counseling, he narrated the entire incident to the police.