ROME, Jan 18, 2023 (BFF/AFP) - Sicilian Mafia boss Matteo Messina Denaro is "seriously ill", a doctor at the health clinic where the fugitive was captured this week said Wednesday.

Messina Denaro, 60, a convicted killer, was caught during a visit to the clinic on Monday after 30 years on the run, after being forced to seek treatment for cancer.

"He is seriously ill. The disease has accelerated in recent months," Vittorio Gebbia, head of the oncology department at the Maddalena clinic in Palermo, told the Repubblica daily.

He underwent surgery for colon cancer in 2020 and 2022 under a false name, according to leaked medical records published in Italian media.

He was detained Monday after detectives discovered through wiretapped conversations with family members that he was ill, and searched Italy for possible suspects of the right gender and age with cancer.

The law enforcement officers checked with Gebbia whether Messina Denaro needed urgent treatment.

"The police asked me if it mattered if the chemotherapy cycle he was set to receive was delayed by a few days, and I signed off on it because such a small delay will have no effect," Gebbia said.

Messina Denaro was moved shortly after his arrest in Palermo to a high security prison in L'Aquila in the Abruzzo region, where he was being held in solitary confinement.

He was expected to be taken for chemotherapy treatment at the San Salvatore hospital in L'Aquila, which has a special unit reserved for this type of prisoner, according to the Corriere della Sera daily.