The elder brother of Raja Raghuvanshi, an Indore-based transport businessman murdered while honeymooning in Meghalaya, on Monday demanded a narco-analysis test on prime accused Sonam's parents and said the family suspects the involvement of more people in the killing.

Police have arrested five people, including Raja Raghuvanshi's wife Sonam, 25 and her alleged lover Raj Kushwaha, 20, for their alleged involvement in the 29-year-old businessman's Murder last month. They are in the Meghalaya police's custody, and an SIT is probing the case.

Talking to reporters during Raghuvanshi's 13th-day death ritual here, his elder brother, Vipin Raghuvanshi, said, "We want a narco-analysis test on Sonam, her parents, brother Govind and sister-in-law."

Sonam is accused of getting her husband killed during their honeymoon with the help of Kushwaha and three others, in a case which has sent shockwaves across the country.

The other three accused, Vishal Chauhan, Akash Rajput and Anand Kurmi, were initially suspected to be hired killers, but the police later found they were friends of Kushwaha.

Vipin Raghuvanshi said, "New videos related to the murder are surfacing one after the other. We believe more people might be involved in my younger brother's killing."

He also demanded that people who posted these videos on social media also be questioned and asked why they had not released the footage earlier.

He, however, expressed satisfaction with the Meghalaya police's probe.

"Our family is happy with the investigation," he added.

Meanwhile, Sonam's brother Govind attended the ritual feast, although the Raghuvanshi's family said he had not been invited.

"I am here to seek forgiveness. If anyone suspects us, we are asking to be investigated. We stand with Raja Raghuvanshi's family," he told reporters.

Govind had also taken part in Raja Raghuvanshi's post-death ritual in Ujjain on 13 June.

However, tensions between Govind and the Raghuvanshi family appear to be growing.

The victim's other brother, Sachin Raghuvanshi, said, "I didn't speak to Govind during the ceremony. He may have come to show sympathy. We did not invite him."

As per the case details, a few days after their wedding, Raja and Sonam left for Sohra (also called Cherrapunjee) in Meghalaya's East Khasi Hills district and went missing on 23 May.

His body was found in a gorge near Weisawdong Falls on 2 June while a search continued for Sonam.

She emerged in Uttar Pradesh's Ghazipur, around 1,200 km away from the crime spot, in the early hours of 9 June and surrendered before police.