Chilean Nobel prize-winning poet Pablo Neruda's remains will be exhumed Monday in a bid by the government to determine if he died of cancer or was poisoned by the Pinochet dictatorship he strongly opposed. The leftist author, who died 12 days after the 1973 military coup that ousted socialist president Salvador Allende and brought General Augusto Pinochet to power, was long believed to have died of prostate cancer. But officials in 2011 started looking into the possibility he was poisoned by agents of the Pinochet regime, as claimed by Neruda's driver. "We are here basically to get started with the activities related to the poet's exhumation. We started with the digging, and we are getting close to the tombstone," investigating Judge Mario Carroza told reporters at a briefing. Neruda's body was to be exhumed at 8:00 am local time (1100 GMT), but tomb opening preparations began Sunday. His remains are in a tomb at one of his homes, which was turned into a museum, in Isla Negra. Police investigators and government forensic experts were on the scene Sunday. Around 1700 local time (2000 GMT) they set up a special tent to shield proceedings from public viewing of the tomb where the remains of his third wife, Matilde Urrutia, are also interred. Neruda won the 1971 Nobel Prize in Literature and is best known for his love poems, as well as his "Canto General" -- an epic poem about South America's history and its people. The Chilean justice system gave the go-ahead for the probe in June 2011 after a complaint was filed by the Chilean Communist Party, of which Neruda was a member. In addition to the driver's accusations, the official complaint cites witnesses who say Neruda was healthy up until the day before his death. They said he did not exhibit symptoms consistent with the advanced cancer to which he was said to have lost his life. The results of the inquiry will find in favor of, or against, the charge made by Neruda's driver and personal adviser Manuel Araya, who believed the poet was slain. Araya's claims spurred on the Communist Party's complaint. Araya says Neruda died after receiving what the driver believed was a suspicious injection at Santiago's Santa Maria Hospital days after the coup that brought Pinochet to power. Neruda's death certificate, to which AFP obtained access, says he died of complications of metastases of prostate cancer. Neruda's family and the official foundation that administers his work have both accepted the official cause of death, saying in a 2011 statement that there was "no evidence or proof" to suggest foul play. Rodolfo Reyes, Pablo Neruda's nephew, speaking at the grave site, said: "We simply want to learn the truth, to get to the bottom of the family truth. Neruda's family wants to know the truth, regardless of whether he died of natural causes or was murdered." "It is not easy for us to explain what they are going to do with the remains, but we think it is necessary," he added.