Parti Keadilan Rakyat (PKR) president Anwar Ibrahim has been linked to an "un-Islamic, vile, insidious and morally repugnant" incident by his former research assistant, in the latest political drama to roil the party.

In a press conference yesterday, Mr Muhammed Yusoff Rawther claimed that his "unwillingness" to "cooperate" with Datuk Seri Anwar during the incident eventually led to a physical assault by his political secretary, Mr Farhash Wafa Salvador, on May 16 at their workplace in Petaling Jaya.

Mr Yusoff did not give details of the incident, which he said took place in October last year. "In my statutory declaration, I have detailed the incident that transpired in the residence of DSAI (Mr Anwar) towards me, attached with all the necessary and relevant evidence. As it has not yet been made public, I can only describe the matter as un-Islamic, vile, insidious, morally repugnant and criminal in nature," the 26-year-old told reporters.

Mr Yusoff also criticised the authorities for failing to take action over police reports he filed against Mr Farhash on May 26, despite producing a medical report confirming injuries he sustained.

"The assault in my working environment is not normal or acceptable and I have since discovered that it is likely related to other incidents that occurred to me during my employment with DSAI," he added.

Dismissing the claims, Mr Farhash accused former PKR member Badrul Hisham Shahrin, popularly known as Chegubard, of masterminding Mr Yusoff's press conference to tarnish the party's image.

Calling it "the work of an unhappy ex-member making a fuss because he has been sidelined", Mr Farhash said it was expected that there would be those out to create unrest and turmoil among the members.

"Chegubard's lifetime membership was terminated three years ago after he was found to be tarnishing the party image and also causing divisions among members... (He) seems to be working with Yusuff (sic)... who was sacked for indiscipline.

"Yusuff is the grandson of the late S. M. Mohamed Idris, who led the Consumers Association of Penang for many years and was also a close friend of Anwar. This is a clear example of someone out to seek vengeance and willing to let himself be manipulated and used to fulfil his own agenda," he said.

The allegations come at the peak of a years-long feud between Mr Anwar and his party deputy, Economic Affairs Minister Azmin Ali.

Mr Anwar has twice been jailed on charges of sodomy, which he has always denied and maintained were politically motivated.