KUALA LUMPUR - Malaysian Prime Minister Najib Razak condemned a grenade attack on Thursday that killed one and injured 12 others in Bukit Bintang and vowed to bring the culprits to justice, The Malay Mail Online reported.

"I condemn in the strongest terms the violence that occurred this morning in Bukit Bintang," said Mr Najib in a brief statement. "Such lawlessness will not be tolerated. The police investigation is underway, and the perpetrators of this crime will be found and brought to justice."

A Malaysian car jockey, 36, was killed and 12 other people, including Singaporean Wong Kim Teng, were wounded when a hand grenade exploded in the tourist section of Malaysia's capital in what police suspect was related to a gangland turf battle.

A hotel worker named Shaun, 29, said he was shocked by the "extremely loud" explosion at about 4:15am when he was on night shift.

"I saw people injured, with blood on their faces and legs. Some were knocked down," Shaun, who did not disclose his full name, told media.

"People were running around. They were helping each other. The police came in five to 10 minutes," he added.

Police said the motive in the incident is being investigated, but another top police official said a gangland feud was suspected. A heavily damaged minivan could be seen at the scene of the incident, which was roped off by a tight police presence. Such incidents are generally rare in Muslim-majority Malaysia, but public concern has steadily grown over rising crime.