The Sessions Court today sentenced a 63-year-old woman Lee Wai Chee to 18 years jail after finding her guilty of attempting to murder her sister's daughter-in-law and torching her house.

Judge Musyiri Peet also ordered Wai Chee's sister, Lee Wai Mei, 66, who was involved in the same act, to be sent to Hospital Bahagia in Tanjung Rambutan at the pleasure of the Yang di-Pertuan Agong.

Musyiri said the sentence against the accused must reflect the offence committed.

"I find that the act was very cruel and should be given heavy punishment," he said.

Wai Chee and Wai Mei were jointly charged with the attempted murder of Yeoh Kar Tin, 45, in Taman Tun Hassan, Bukit Mertajam, near here on May 8, 2012.

The two sisters were also charged with two counts of causing mischief and one count of injuring the victim.

The court dismissed the charges against Wai Mei on the grounds of insanity and ordered her to be sent to Hospital Bahagia.

Wai Chee was also sentenced to 18 years jail on the second and third charges, with the sentences to run concurrently from today.

Lawyer Y. Anbananthan represented the two sisters while Kamaliza Md Zin prosecuted.