One man has been killed and a dozen other people wounded after a hand grenade exploded in a tourist section of Malaysia's capital in what police suspect was an incident related to a gangland turf battle.

Police said a parking attendant who was the most seriously hurt in Thursday's incident later succumbed to his injuries in hospital following the pre-dawn blast outside a bar in the bustling Bukit Bintang neighbourhood.

"We believe it was a hand grenade that was placed in front of a pub," Kuala Lumpur police chief Tajudin Mohamad Isa told the AFP news agency, noting that an unexploded grenade also was found.

Zainol Samah, police chief of the district where the incident took place, told AFP there were a total of 13 casualties.

Eight other Malaysians were hurt along with two Chinese nationals, one Singaporean, and one Thai, he said.

Other police officials reported 14 total casualties, including the deceased.

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 Malaysia, but public concern has steadily grown over rising crime.

Those fears spiked last year with an explosion of gun violence that authorities blamed on rival gangs battling over influence, prompting a tough anti-crime crackdown.