A man has gone on the run after allegedly killing his lover so his partner would not find out she was pregnant with his baby.

Larin Kathleen Oliveira da Silva, 22, was reported as missing on 12th November and her decomposing body was found in a rural area of the municipality of Bandeirantes in the Brazilian state of Parana on Monday, 15th November.

The police have identified her ex-boyfriend Fernando Amaro de Oliveira as the main suspect, and consider him a fugitive after he allegedly went on the lam. A preventive arrest warrant was issued against him on Wednesday, 17th November.

According to the news site O Globo, the suspect spent the early hours of Saturday morning (13th November) at a party with his partner. Given the state of the victim’s body when it was found on Monday, it is believed she had already been killed at the time of the party.

The police chief responsible for the investigation, Michael Araujo, said the victim became pregnant about four months ago during a fling with the suspect after their relationship ended about a year ago.

The fling took place while the suspect was already engaged to his new partner.

Araujo said the victim withheld her pregnancy from Fernando for a while before informing him recently that he was the father.

He allegedly told his former lover to terminate the pregnancy and even went out and bought abortion medication for her to take.

However, the victim refused and vowed to keep the child before going missing at around 7pm on Friday, 12th November.

She was found in a wooded area in an advanced state of decomposition on Monday with a perforated wound below the breast.

Forensic experts are still determining the cause of death as well as if the foetus was removed during the alleged murder, according to O Globo.

Fernando has since gone missing and is considered a fugitive as the investigation continues.