The Singaporean man arrested for the suspected killing of fellow Singaporean Audrey Fang, 39, in Spain, has been detained at a Spanish prison and is accompanied at all times by an English-speaking inmate.

Singaporean Mitchell Ong, 43, is in pre-trial detention in Sangonera prison in Murcia, Spain following his arrest on Apr. 16.

This was after Fang was found dead with more than 30 stab wounds in Murcia on Apr. 10.

'Trusted prisoner' assists him daily: Lawyer

Ong only receives visits from his lawyer Carolina Flórez de Quiñones, CNA reported.

Carolina said Ong is "in a state of distress" and he does not speak Spanish.

A "trusted prisoner" who is fluent in English accompanies him daily to help him with day-to-day matters, she explained.

Carolina said Ong has yet to provide a statement to the authorities and at the moment, there are no plans for him to voluntarily do so.

She also said he had entered the country as a tourist.

Found dead on holiday

Fang, 39, had been on a solo trip in Spain and was staying at a luxury hotel in Xàbia, Valencia.

She was last spotted walking out of the hotel on the night of Apr. 9 with her personal belongings still in her room.

A body, which was later identified to be Fang's, was found the next day in a lorry park at Abanilla, some 150km away from where she was last seen.

She had allegedly been stabbed over 30 times.

Ong was arrested on Apr. 16 at the Eurostars Lucentum hotel in Alicante, local Spanish paper La Verdad reported.

He was found with Fang’s mobile phone and €3,760 (S$5,473) and US$1,000 (S$1,351) in different currencies during his arrest.

What investigations turned up

Police investigations revealed that a grey Nissan rented by Ong was caught on surveillance camera near where Fang's body was found.

The keys to the car were found on Ong during the arrest.

It was also reported that Ong had bought a vacuum cleaner and a magistrate overseeing the case noted that it was "very suspicious" for the rental car to be cleaned, La Verdad reported.

Fang's family later discovered that she had bought two investment-linked insurance policies in 2015 from an agent, Ong Cheong Yi.

The name is Mitchell Ong's Chinese name.

Authorities are also investigating a Central Provident Fund (CPF) nomination note found on Fang's iPad in her hotel room.

The note, dated Mar. 24, stated that CPF money was to be left to an unknown person known to Fang, who is a "long-time friend and trusted confidant".

It also indicated that the person had provided a “friendly loan of US$50,000 (S$67,594)" based on "past friendship".

CNA reported that according to sources close to the investigation, Ong had no known links to the region of Murcia or to Alicante, where he stayed prior to the arrest.

Ong has declined to comment since his arrest.

If convicted, he could face 20 to 25 years in jail in Spain.

Top image from Guardia Civil / Google Maps