KUCHING (THE STAR/ASIA NEWS NETWORK) - Police have ruled out terrorism or criminal acts in the explosion at CityOne Megamall in Kuching, in the East Malaysian state of Sarawak, on Tuesday (Dec 4) which left three people dead and 41 others injured.

Sarawak Deputy Commissioner of Police Mohd Dzuraidi Ibrahim said investigations so far found no militant elements.

"There are also no criminal elements involved. We have classified the case as sudden death," he told reporters at the scene of the blast on Wednesday.

He said the Fire and Rescue Department was still investigating the cause of the explosion.

The department's state director Khirudin Drahman said its personnel, as well as a sniffer dog from its K9 unit, were at the scene to verify the initial assumption that the explosion was caused by a gas leak.

"We have taken gas samples from the scene to be analysed in our lab. From the pattern of the explosion that we saw on CCTV footage as well as the victims' injuries, it seems to confirm our initial findings and hypothesis," he said.

The explosion occurred at about 3.30pm on Tuesday at the NeNe Chicken outlet on the ground floor, which was being renovated for its opening the next day.

Mr Stephen Long, the director of CityOne developer Kenbest conveyed his condolences to the families of the dead.

"Our workers were doing the final touch-up and getting everything ready for the opening, but one explosion changed the whole scenario. What I can do now is to take care of the welfare of our colleagues and staff in hospital. I'll give my assistance and support, emotionally and also financially, to those in hospital and the families of the deceased," he said.

His son-in-law Johnny Lau, who was in the kitchen at the time, suffered burns on 20 per cent of his body and was hospitalised at the Sarawak General Hospital.

Mr Long's wife Sim Ewe Kee was slightly hurt by a falling steel structure and was discharged from hospital on Tuesday.

"Safety at CityOne is always our priority. We are serious about safety. That's why our family members were also inside," Mr Long said.

The mall, he said, would remain closed until clearance was given by the authorities.

Meanwhile, NeNe Chicken Malaysia said it was working towards obtaining a full report of the incident.

"We are working with our CityOne outlet licensee and the CityOne mall management and giving our full cooperation to aid those affected and to help investigations," it said in a statement.

The company said it was "deeply saddened" by the loss of three lives and the injuries suffered by others.

"We are extending assistance to those injured and affected by the incident, and our thoughts and prayers are with the families of the deceased," it said.

It also called on the public to respect the privacy of the families involved and not to share unconfirmed information.

In Butterworth, a woman said to be the grandmother of Mr Chin Hsien Loong, 29, who was among those killed in the explosion, pleaded for privacy.

When approached at her house, the woman told reporters to give them space and not to take any photographs.

"Please respect our privacy. We are terribly upset over the incident," she said.