Both the accused have been arrested, they said.
On February 4, police had registered a case of accidental death of Yogesh Kende (47), a resident of Kolshet area in Thane city.
However, sensing something amiss, police conducted a probe into the death and later it was found that the victim was murdered, senior police inspector S D Jadhav said.
During the course of investigation, police ascertained that the victim's wife was in love with a 24-year-old carpenter staying in her neighbourhood.
The woman and her paramour then hatched a conspiracy to kill Kende. Accordingly, the duo smothered him on February 4 with a pillow and showed it as a case of natural death, police said.