South African police have opened a new investigation into the 1986 airplane crash that killed Mozambique’s Marxist president and more than 20 others, an official said Wednesday, an incident many have blamed on the former apartheid government.President Samora Machel, who had led Mozambique from its independence in 1975, died when the twin-engine Tupolev 134-A crashed on rain-swept hills just inside of South Africa’s eastern border. His widow, Graca Machel, later married South African anti-apartheid icon Nelson Mandela, who promised while president that anyone found guilty of causing the crash would be "severely punished.”It’s unclear whether new information sparked the investigation, which is being led by the South African Police Services’ elite Hawks investigative unit. Capt. Paul Ramaloko, a spokesman for the Hawks, told The Associated Press on Wednesday that investigators had begun a formal inquiry into the crash, but offered no details."Our investigation is still at an early stage,” Ramaloko said. "We will be able to report progress once we have something to talk about.”The crash happened Oct. 19, 1986, as Machel returned from Zambia after a meeting with a group of other black heads of state in the region called the Front Line States. At the time, Mozambique hosted exiled members of the African National Congress, which would become South Africa’s governing party. South Africa’s apartheid government helped arm and fund the rebel group called the Mozambique National Resistance, or RENAMO, to keep Mozambique ensnared in a civil war and unable to help South African militants and opposition leaders living there.Ten people survived the crash, which happened near South Africa’s border with Mozambique and Swaziland in the Lebombo Hills. A report released a year after the crash by a panel commissioned by South Africa’s white-ruled government blamed the disaster on the plane’s Soviet crew, which the panel said ignored safety procedures as a storm forced pilots to fly using their instruments due to poor visibility. When an alarm sounded that the plane was nearing the ground, the crew likely ignored it as they thought they were close to landing in Maputo, the capital of Mozambique, the panel said.But they weren’t, as pilots somehow had locked onto a different radio frequency in the opposite direction. Some experts later said the apartheid government may have used false signals from navigation beacons to lure the plane off course. An investigator for the Truth and Reconciliation Commission, a panel that investigated apartheid-era atrocities, said that their investigation suggested that the South African Defense Force, military intelligence or special forces operatives had been involved in the crash, which Graca Machel has in the past called an assassination.