A man posing as a police officer and armed with a handgun raped a New South Wales woman on her last day of isolation and told a second woman she would go to prison if she did not have sex with him, a court has heard.

Key points: One of the victims, a New South Wales woman, was on day 14 of isolation after arriving in SA

One of the victims, a New South Wales woman, was on day 14 of isolation after arriving in SA The man allegedly handcuffed the woman, demanded money and raped her

The man allegedly handcuffed the woman, demanded money and raped her The man allegedly raped a second woman after also threatening her with a handgun

The 31-year-old — who cannot be named for legal reasons — has been charged with two counts of rape and two counts of impersonating police after the alleged attacks at an Adelaide city hotel last Friday.

On Monday he appeared in the Adelaide Magistrates Court via video link from the police cells, seeking release on home detention bail.

The application was opposed by prosecutors.

Prosecutors told Magistrate Greg Fisher that the first victim, from New South Wales, answered the door to what she thought was a police officer about 8:30pm.

"She's been in isolation, she's from New South Wales — it was day 14 of her isolation," he said.

"There was a knock at the door and the male provided a police ID card.

"He said he was checking on her due to the coronavirus so she let the male in."

The prosecutor told the court the man handcuffed the woman to the sofa before showing her a handgun concealed in his jacket and asking for money.

The court was told she handed over $400 and the accused showed her the gun a second time and asked for more money.

She handed over $6,200, the court heard.

Prosecutors said the man then raped the woman.

"She stated to him that she would have no money to buy food so he handed back $400," prosecutors told the court.

The court was told the second victim was waiting in her hotel room for her travel companion to return about 10:45pm on the same night, when he walked in with a "police officer".

"He showed her the handgun," the prosecutor said.

"He told her that she would go to prison if she was not quarantining and the only way she would not go to prison is if she had sex with him."

Prosecutors said the man told the male travel companion to stay in the bathroom while he allegedly raped the woman.

The man's lawyer, Andrew Ey, told the court his client denied the allegations.

Magistrate Fisher refused to order a home detention report and rejected the application, saying the allegations were far too serious.

The man will be back before the courts in July.