A couple and their three children were found dead at their residence in the Lisadi Gate Police Station area Meerut on Thursday night, police said.
Meerut Senior Superintendent of Police (SSP) Vipin Tada, who visited the crime scene, said the police received a call about a locked house.
Upon reaching the location, the officers found out that the house had been locked from outside, he added.
"After gaining access through the roof, they found the bodies of Moin, his wife Asma and their three daughters -- Afsa (8), Aziza (4) and Adiba (1)," Tada told reporters.
"The manner in which the house was locked suggests that the individual involved in the crime may have been someone known to the family," he said.
WATCH: Family of 5 found dead in locked house
The SSP said the preliminary investigations point towards an old enmity as the possible motive behind the incident.
"A detailed investigation is underway," he added.
The SSP further said the legs of one of the deceased were found tied with a bedsheet, adding a forensic team and senior officers are collecting evidence from the site.
The family had recently moved to the area and the police are investigating their background to find out more details, he added.
Moin, a mechanic by profession, and his wife Asma had been missing since Wednesday.
Moin's brother Salim was the first to witness the horrifying scene.
Extremely concerned over his brother's whereabouts, Salim arrived at Moin's house with his wife.
After several unsuccessful attempts to open the door, they forced entry with the help of neighbours.
They found the bodies of Moin and Asma lying on the ground, while the bodies of the children were hidden in a bed box.
BURARI MYSTERY: Murders or Suicides?
Kerala family of 4 found dead in US home
US: Wealthy Indian-origin couple, daughter found dead
Burari deaths: Handwritten notes reveal chilling details
Burari deaths: Relatives dismiss suicide theory, allege family was killed