A popular local actor and a woman who worked with his company are now locked in defamation claims against each other.

Local celebrity Edmund Chen, 56, has accused public relations and marketing consultant Karen Ho Kai Lun of sending defamatory WhatsApp messages to at least 11 people, including his business clients, between February and April.

The actor, who is known as Mr Tan Kai Yuan in court papers, is director of event production company Asiatainment.

Ms Ho, 30, is accusing him of defaming her via Facebook posts.

According to court documents obtained by The Straits Times, Mr Tan felt Ms Ho allegedly defamed him after she was told they would no longer be working together.

He is claiming damages for libel from Ms Ho and filed the case against her on April 28.

Ms Ho is accusing him of repeatedly publishing comments she alleged were defamatory to her on his Facebook page in April.

She is also claiming damages and filed the case against him on May 17.

The court documents for both parties do not specify the amounts each is seeking.

Mr Tan is represented by lawyers Samuel Seow Theng Beng and Shaun Marc Lew from Samuel Seow Law Corporation.

His amended statement of claim dated May 4 states that Mr Tan is the author and illustrator of a book titled My Little Red Dot.

The claim says: "In or about (September last year, Asiatainment) agreed to engage (Ms Ho) for her services to promote and sell (the book) on behalf of the company in exchange for valuable consideration." But the company subsequently took issue with how Ms Ho represented herself to third parties when promoting and selling the book.

On Feb 14 this year, Mr Tan told her that they would no longer be working together from the following day. The claim states: "At all material times, (Ms Ho) was never an employee of (Asiatainment) and no notice period was therefore necessary." It also says that after this, she allegedly sent out the WhatsApp messages which Mr Tan claims were defamatory.

Mr Tan's claim stated that he came across as having "acted irresponsibly" and was "avoiding" his company's clients.

Ms Ho is represented by lawyer Nicolas Tang Tze Hao from Farallon Law. Her statement of claim states that Mr Tan posted alleged defamatory remarks against her on Facebook on four occasions between April 11 and 21.

Her claim states that some of the words on his Facebook post made it seem that she was a criminal and a cheat. The claim goes on to say: "At the relevant times, Facebook had millions of users, all of whom had free and open access to the words.

"It can be inferred that a large and unquantifiable number of users in Singapore and around the world read the articles."

Her claim also states that the words were republished on other platforms such as the national press and on various websites.

She then demanded, through her lawyers, that he publish an apology on his Facebook page, and several newspapers are to be alerted to the posting. The cases are pending.