KUCHING (THE STAR/ASIA NEWS NETWORK, BERNAMA, AFP) - Three people were killed and dozens injured on Tuesday (Dec 4) when a powerful explosion rocked a shopping mall in Kuching, in the east Malaysia state of Sarawak.

State fire and rescue department director Khirudin Drahman confirmed that three men were killed in the 3.30pm blast at CityOne Megamall.

The deceased were identified as O Kui Lim, 49, and Tchee Kiam Jong, 24, both from Sarawak, and Chin Hsien Loong, 29, from Penang.

Mr Khirudin noted that two of the deceased were workers at the Nene Chicken food outlet on the ground floor of the mall. The outlet was being renovated and was scheduled to officially open on Wednesday (Dec 5).

Another 26 people were injured in the incident, with four of them in critical condition.

The cause of the explosion is still being investigated, but initial reports said it could have been caused by a leaking gas tank.

Mr Wan Abdul Mubin, head of the Kuching fire and rescue department, told Agence France-Presse that 39 officers were scrambled to the scene after receiving an emergency call.

"It is one of the worst tragedies in the state in years. But it is not a bomb," he said.

A video clip of the aftermath showed the facade of the store torn apart, with some people screaming for help.

"I was purchasing a pizza in front of the shop when suddenly a strong explosion occurred," Mr George Sting, 39, told Bernama. "The workers in the shop immediately ran out," he said, adding that some were seriously injured.

A shop worker known as Niedazaie said she heard a loud sound like an explosion some time after 3pm.

"It was very loud. At first I thought it was the weather but it sounded too loud. Then I felt some shaking and we were told to evacuate the building," she said.

Ms Wina Simion, 46, said she was sitting nearby with her family members when the incident occurred.

"Our family was enjoying pizza at a restaurant here, and suddenly, we were shocked by the explosion from the store which also caused our table to fly up," she said.

Other witnesses told The Star that the explosion caused the ceiling at a section of the mall to collapse.

A victim, who only wanted to be known as Benny, said he was installing beverage equipment when the blast happened.

"The wall fell and hit me. Everyone was in a panic," he said, adding that there were about 20 people in the vicinity during the time.

Spanning 1.5 million square feet spread across four stories, CityOne houses 400 retail outlets and is Sarawak's largest commercial development.

The mall announced on Tuesday that it was closed to the public with immediate effect due to the explosion.