Diego Maradona's personal doctor is being investigated for possible negligence in the Argentina legend's death last week.
Justice officials ordered the search of properties of Dr Leopoldo Luque on Sunday, a local prosecutor's office said.
The search order was requested by prosecutors in the affluent Buenos Aires suburb San Isidro and signed by a local judge.
Investigators are trying to establish if there was negligence in the treatment of the retired footballer, one of the greatest players of all time.
"Yesterday [Saturday] the investigation and substantiation of evidence continued with the taking of statements from people including direct relatives of the deceased," the prosecutor's office said.
"By virtue of the evidence that was collected, it was considered necessary to request searches at the home and office of doctor Leopoldo Luque."
About 60 police officers took part in the raids at both properties.
Local TV stations showed Dr Luque at his home while the search on the outskirts of Buenos Aires took place.
Maradona, 60, died of a heart attack at his home in Tigre last Wednesday, where he was recovering from brain surgery.
Prosecutors allege that Maradona was not given the appropriate discharge to leave the clinic, and have concerns over his follow-up care.
Argentinian media are reporting Dr Luque could be questioned as an "imputado", someone who is under official investigation on suspicion of possible malpractice or negligence, rather than a simple witness.
It could lead to a charge of wrongful death if he were found guilty.
The doctor in charge of administering Maradona's medication, as well as at least one other person inside the house at the time of death, could also be charged.
Dr Luque's home and surgery were being searched for documents that could determine whether there were any "irregularities" during Maradona's treatment at home, La Nacion newspaper quoted a judicial source as saying.
The searches come a day after Maradona's daughters, Dalma and Giannina, questioned whether the medication their father was receiving was appropriate.
Matias Morla, Maradona's lawyer, has called for a probe into the emergency response to the 1986 World Cup winner's death.
"The ambulance took more than half an hour to arrive, which was a criminal idiocy," Mr Matias said on Thursday in a Twitter post.
It emerged over the weekend that the first ambulance took 11 minutes to reach the residence in a gated community just outside Buenos Aires.
Dr Luque was not at the rented home Maradona was using when he died.
A recording of the call Dr Luque made to the emergency services, stating Maradona had suffered a suspected cardiac arrest, has been leaked to Argentinian media.
Although he had battled health problems, including obesity and drug addiction throughout his life, news of the former Barcelona and Napoli player's death shocked the footballing world and led to an outpouring of tributes from the likes of Pele and Lionel Messi.
Maradona, who represented Argentina at four World Cups and coached the Albiceleste at the 2010 finals in South Africa, had undergone surgery to remove a blood clot on his brain at the Olivos clinic in Buenos Aires on November 3 and was discharged eight days later.
He did not speak to the crowd of media and chanting fans gathered outside in masks as he left the clinic by ambulance shortly after Dr Luque announced he could go home.
Dr Luque had earlier published on Instagram a photo of himself hugging the 60-year-old, who had a bandage on his head.
The football legend was laid to rest after a ceremony attended by family and close friends at the Bella Vista cemetery outside Buenos Aires on Thursday.
Clashes broke out as thousands turned out to pay their respects to one of the world's greatest football stars.