SANTIAGO (Reuters) - Spanish researchers investigating the early ‘70s death of Chilean poet Pablo Neruda to determine if he was poisoned, have found no conclusive evidence of foul play, according to an initial report handed to the investigating judge.

Tourists visit the tomb of Chilean poet and Nobel laureate Pablo Neruda inside the grounds of his house-museum before the exhumation of his remains in the coastal town of Isla Negra, about 106 km (66 miles) northwest of Santiago April 7, 2013. REUTERS/Eliseo Fernandez

The Chilean government reopened the investigation into his death in January, with new tests designed to look for protein damage caused by chemical agents, suggesting poisoning.

Forensic experts at the Universidad de Murcia found three types of protein in the remains of Neruda, a Nobel laureate, two of which could be explained by advanced prostrate cancer, said the report seen by Reuters on Thursday.

The source of the third protein was not immediately clear, but could be due to natural causes such as infection, or posthumous manipulation of the remains, the report said.

An expert panel will now examine the evidence, while a further genomic analysis is still pending.

Neruda, famed for his passionate love poems and staunch communist views, is presumed to have died of cancer days after a coup in 1973 that ushered in the brutal dictatorship of Augusto Pinochet.

However, the poet’s chauffeur has claimed that Pinochet’s agents took advantage of Neruda’s illness to inject poison into his stomach as he lay in hospital.

Initial tests on his exhumed body in 2013 found no evidence of the remains of poison.

Neruda’s family and supporters have been divided over whether the case should be closed and his remains returned to his grave near his coastal home of Isla Negra, or whether researchers should continue carrying out tests.

“The data analysis requires a dose of caution to avoid jumping to conclusions in the absence of additional information which we currently lack,” it said.