An ex-WA Police senior constable has appeared in court charged with more than 100 sexual offences, accused of drugging and raping women he met online in a series of alleged crimes dating back to 2010.

Key points: Adrian Trevor Moore allegedly met the women via dating websites

Adrian Trevor Moore allegedly met the women via dating websites A court has been told the alleged offences dated from 2010 to 2017

A court has been told the alleged offences dated from 2010 to 2017 The former officer did not enter a plea when he faced court

WA Sex Assault Squad detectives charged 50-year-old Adrian Trevor Moore from the Perth suburb of Kelmscott following extensive investigations into what they called "predatory sexual behaviour".

It is alleged that since 2010, Mr Moore met numerous women through dating websites and sexually assaulted them during a number of dates.

Police allege a stupefying substance was used against the women at least eight times.

Adrian Trevor Moore has been charged with more than 100 offences. ( ABC News )

Mr Moore is facing a total of 108 charges relating to alleged attacks on eight women in their mid to late 40s, including:

34 counts of sexual penetration without consent

34 counts of sexual penetration without consent 32 counts of aggravated sexual penetration without consent

32 counts of aggravated sexual penetration without consent Eight counts of aggravated indecent assault

Eight counts of aggravated indecent assault Eight counts of stupefying someone in order to commit an offence

Eight counts of stupefying someone in order to commit an offence Two counts of aggravated assault causing bodily harm

Two counts of aggravated assault causing bodily harm Three counts of aggravated sexual coercion.

The ex-officer's alleged crimes dated back to 2010. ( ABC News: Adam Haynes )

WA Police said they believed a number of other alleged victims were yet to come forward.

Mr Moore resigned from the WA Police Force in May 2018 after being charged initially by the Internal Affairs Unit.

No plea and no bail application in court

The former officer appeared in the Perth Magistrates Court this morning to face the 108 charges, which were read to him by Magistrate Belinda Coleman in "a truncated form".

They confirmed the offences were alleged to have been committed between 2010 and 2017, when he was still a serving police officer.

Mr Moore quit the force in 2018 after being charged initially by the Internal Affairs Unit. ( ABC News )

Mr Moore was not required to plead to any of the counts and spoke only to acknowledge that his understood the charges.

Defence lawyer Mark Andrews said his client was not applying for bail on Thursday, but was likely to do so at his next court appearance in three weeks.

Speaking outside court, Mr Andrews said he had only been instructed by Mr Moore shortly before his court appearance and he was unable to make any detailed comment about the case.

He said that given his client was a former police officer, he hoped the authorities would ensure his safety in custody.

"They're aware of his prior position and I'm confident those arrangements would have been put in place," he said.

Sex assaults allegedly recorded on video

WA Police Acting Inspector Simone Van Der Sluys said Mr Moore was accused of using his power and position as a member of the force to assault the women.

Acting Inspector Simone Van Der Sluys appealed for any other women who had been in touch with Mr Moore to come forward. ( ABC News: Benjamin Gubana )

Police allege he used several well-known dating apps to lure the women, sometimes under nicknames.

Acting Inspector Van Der Sluys described the allegations against the former senior constable as "extremely serious".

"It is alleged on a number of these dates with these women, he sexually assaulted them and he video recorded a number of these offences.

"I'd like to stress [this] as a reminder to both men and women of the dangers that exist with online dating applications, and just to remain vigilant of your own personal safety."

Acting Inspector Van Der Sluys said she believed the women allegedly assaulted by Mr Moore were reluctant to come forward due to him being a serving police officer at the time.

She said the investigation was not "anywhere near finished" and police were "still working" with other alleged victims.

"We are victim focused at the Sex Assault Squad and it is our job to support and help any of the potential victims with allegations that they make. We will investigate every allegation seriously," she said.

"I'm here before you today to urge any other women out there who've had dates with this man, that have had any sexual relationship, even contact via online dating applications, any information, please contact police.

"If you're reluctant to come forward to police, your information may be anonymous through Crime Stoppers."

Women who have concerns they have been a victim of an assault but who do not wish to speak to police can seek support from the Sexual Assault Resource Centre on (08) 6458 1828.