Hyderabad: The Hyderabad police have made significant progress in uncovering the murder of Indian Engineer K. Prasad, his wife, and two children in a city lodge by arresting six suspects, including a female relative.

The investigations were focused on the possibility of a dispute between Prasad and a female relative over money which he had sent from Dubai for a fixed deposit and also towards the premium of an insurance policy.

According to sources, an amount of Rs1 million (Dh44,450) was at the heart of the dispute.

The police managed to reach the woman in Visakhapatanam after painstakingly going through the records of calls made and received on Prasad's mobile phone.

Though the killers had taken Prasad's cellphone, investigators were able to gather details by using his cellphone number.

The phone records showed that a female relative had made frequent calls to Prasad's phone ever since he arrived in Hyderabad on July 24.

Police also discovered that before the murder, the victims along with two other couples had visited the I-Max theatre in Hyderabad to watch a movie.

Investigators later went through the footage of the movie theatre's closed-circuit television (CCTV) cameras and spotted the suspects including the woman, who eye witnesses described as a "fat lady".

Police also identified the two couples from the CCTV footage of Secunderabad railway station where they and Prasad's family had disembarked after leaving their home town Razole in East Godavari district.

At the moment, police are interrogating Prasad's female relative as well as the five other suspects to try establish the motive for killing Prasad and his entire family.

Prasad had been working as an engineer for the last ten years at the Dubai Petroleum Company.

He and his family had returned to Hyderabad to attend the funeral of his mother.

Prasad was scheduled to fly back to Dubai the same night that he and his family were killed at the RAK Royal Lodge in Secunderabad.