KUALA LUMPUR (Reuters) - A Malaysian court on Friday overturned the conviction of two policemen found guilty of shooting and blowing up a Mongolian model linked to a former associate of Prime Minister Najib Razak.
The release of the officers, who were part of Najib's personal security detail at the time of the 2006 murder of 28-year-old Altantuya Shaariibuu, appears to distance the prime minister from the case.
But the ruling also revived public outrage over her mysterious death and raises further questions as Najib prepares for a possible leadership challenge from within his ruling party in October.
A three-member panel on Malaysia's Court of Appeal unanimously decided that the conviction of Chief Inspector Azilah Hadri and Corporal Sirul Azhar Umar had been unsafe.
Among the grounds cited were that a key witness, Najib's then aide-de-camp, hadn't been called to give evidence and that a police diary that may have given one of the men an alibi hadn't been considered.
"It is our judgment that the cumulative effect of the non-directions by the learned trial judge rendered the conviction of the appellants unsafe," state news agency Bernama quoted one of the three judges, Justice Tengku Maimun, as saying.
The high court that found the policemen guilty and sentenced them to death in 2009 never established a motive for the crime. Najib's one-time close associate, Abdul Razak Baginda, a political analyst, was charged with abetting the murder but was acquitted in 2008.
Civil society groups and Malaysia's political opposition have alleged that Altantuya's killing was connected to her role as an interpreter and associate of Razak Baginda in Malaysia's purchase of two Scorpene-class submarines from French shipbuilding giant DCNS in 2002.
Najib, who was defence minister at the time, has strenuously denied allegations of corruption in the purchase and of having any links to the murdered woman.
But his government has declined opposition requests for a public inquiry into the case - which is currently the subject of a French investigation - and has only given brief responses to questions raised in parliament.
Documents, including records seized by French prosecutors in a raid on DCNS's offices, detail payments made to two companies set up by Razak Baginda, but there has been no evidence linking Najib directly to corruption in the deal.
"The verdict this morning calls for nothing short of full and fresh investigations," said Cynthia Gabriel, an activist with the rights group SUARAM, which is a plaintiff in the French investigative court case.
"SUARAM questions whether her brutal death was linked to the allegations of corruption in the Scorpene deal," she added.
Many people took to Twitter and other sites to voice anger and disbelief over the still unresolved saga. Altantuya was blown up with military-grade explosives.
"A woman was killed using explosives. No one is found responsible for her death. Where is justice?" tweeted one person with the username @1Obefiend.
Reporting By Siva Sithraputhran; editing by Stuart Grudgings and Nick Macfie