Thiruvananthapuram: An Army personnel was arrested on July 27 night for allegedly killing his 30-year-old girlfriend and burying her body in the backyard of his under-construction house, an official said.

Based on a tip-off, Thiruvananthapuram Police arrested Akhil, a prime accused in the case, from Thiruvananthapuram International Airport.

"We received information that he will reach the airport in the night. We were monitoring his movements closely. He is being interrogated and will be produced before the court tomorrow," the official said, according to a PTI report.

According to police, Akhil and Rakhi were in a relationship for over six years. Rakhi started quarrelling with him when she was informed that he was going to marry another woman.

To get rid of Rakhi, Akhil and his brother Rahul hatched a conspiracy to kill her. They strangulated her to death and buried her body in the backyard of their under-construction house, police said. 

The matter came to light when police found the decomposed body of Rakhi on July 24.

Earlier in the day, police had arrested Rahul in connection with the case.

Besides Rahul and Akhil, their friend Adarsh, a suspect in the case, was also taken into custody, police said.