Police said couple was deceived into believing that they would be married.
On their return, the girl's brother Pramod, who was against the match along with two of his friends — Sudhanand and Bunty Sharma, persuaded Ojha to accompany them to Muraddgaunj in Auraiya district of neighbouring Uttar Pradesh.
The trio poisoned Ojha at Muraddgaunj on June 20.
A couple of days later, they shot dead the girl at her Bhind residence and tried to pass it off as a suicide, police said.
"We had been suspicious of Pramod's involvement right from the start. On Sunday we arrested the three and recovered a motorcycle, ATM cards, mobile phone and clothes of Ojha from Pramod's possession," said Dr Ashish superintendent of police Bhind, terming the murders as revengeful killings.
"Police cracked the case on the basis of Pramod's suspicious statements, his past records, information gathered from his neighbours."