An autopsy on lawyer Margaret Mifsud yesterday indicated that she might not have died of natural causes as initially thought, sources said.

However, the exact cause of death of the 31-year-old mother of two, whose body was found in her car in Baħar Ic-Ċagħaq on Thursday afternoon, remains a mystery because the autopsy results were deemed to be inconclusive and the police are waiting for further test results.

Dr Mifsud’s mother, Tessie, was not surprised that the death was not a natural one, insisting that her daughter was a “very healthy woman” who “lived for her children”.

“She was as fit as a fiddle... We, the family, are very irritated that the media has been saying she died of a heart attack. It’s not the case,” her mother said.

“She was a good girl,” she said, adding that she last saw her on Wednesday at about 8 p.m. before she left for a colleague’s farewell party.

Police sources noted that Dr Mifsud’s death was being treated as “suspicious” even though the scene of the crime yielded no signs of foul play, substance abuse or self-harm.

Not long after the discovery of the body, the police arrested Dr Mifsud’s former partner and the father of her children. He was still being questioned yesterday.

Sources said Libyan national Nizar El Gadi was being treated as a suspect. Dr Mifsud had reported him to the police accusing him of trying to strangle her last month, the sources added.

Dr Mifsud gave a colleague a lift home following a farewell party in Xemxija on Wednesday night. Her colleague lived in Buġibba. After dropping her off at about 11.30 p.m., Dr Mifsud was meant to head home to Birkirkara where she lived with her parents and two daughters.

The following morning her mother reported her missing because she had not returned home. Her body was discovered at about 2 p.m. during a routine police patrol.

Her car, a dark blue Daihatsu Sirion, was parked between some bushes in a dirt road in Baħar Iċ-Ċagħaq in front of the sea and was clearly visible from the Coast Road.

Dr Mifsud was sitting in the driver’s seat and was fully clothed, the sources said.

No handbag was found in the car even though colleagues said she carried a clutch bag during the farewell party.

One colleague, who was with her on Wednesday night, said that about 14 people who worked in an accounting and auditing firm met to bid farewell to a secretary who was changing jobs. Dr Mifsud picked up the secretary from Buġibba at about 8.15 p.m. and they headed to Fortress, in Xemxija.

“There was nothing different about her that evening. She was normal… joyful as usual, like she was at the office,” one colleague said.

When the get-together was over, Dr Mifsud took the secretary back home.

At about 4 a.m., Dr Mifsud’s mother sent a text message to the secretary asking whether she knew where her daughter was. The secretary called her and told her they had parted ways late the night before.

In the morning (on Thursday) at the office, the secretary told colleagues what had happened.

She told them she was worried something had happened to Dr Mifsud who had not returned home and did not show up for work.

People who tried phoning her found her mobile phone switched off. Their worst fears were realised when news of her death emerged in the media.