Riccardo Viti, a 55-year-old plumber, was arrested at his home on via Locchi in the northern outskirts of Florence at dawn on Friday morning.
Viti apparently made no protest as he was arrested and later confessed to the murder during questioning, Corriere della Sera reported.
At the moment of the man's arrest, Viti was reported to have said "I'm finished. No one can save me now".
The 55-year-old faces charges of murdering 26-year-old Romanian prostitute Andrea Cristina Zamfir, whose naked body was discovered under a bridge in the Ugnano district by a cyclist on Monday tied to a horizontal bar in a position similar to that of crucifixion. She had been raped and left to die.
Viti also faces charges of sexually assaulting at least three other prostitutes.
During the search of the man’s home, police said they had also found tape matching that used to bind the murdered prostitute, which was linked to the Careggi hospital just minutes from Viti’s home.
The arrest comes after police said they had found the same DNA in three separate cases investigated in connection with the killing.
The DNA, which was discovered on the tape used to bind the women, concerns a case from July 17th 2011 in Calenzano, a case from March 28th 2013 in Ugnano and another from February 21st 2014, also in Calenzano.
Police are also investigating possible links with four other cases dating back as far as 2006.
Investigators, however, have not ruled out that there could be more cases linked to the killing.
Through interviews with five of the women, including one with a 46-year-old prostitute who was sexually assaulted in a similar case in March 2013, police were able to piece together a physical description of the man.
Quoted in Corriere della Sera following Viti's arrest, the suspect’s mother said: “I don’t know what happened, what my son has done. Ask the police. I only know that I am in the deepest despair.
“They just told me that he confessed. I didn’t know anything. I wasn’t aware of anything. I thought he was a good boy but if he did what he did I can’t defend him. I don’t want to talk about it anymore. I’m just in despair.”