05/03/2013 (Reuters) - Three Malaysian palm oil refineries with a combined capacity of 1.8 million tonnes plan to halt operations if a Malaysian military attack on an armed Filipino group on Borneo island drags on, refinery officials told Reuters on Tuesday.

"The three companies owning these refineries are looking to cease operations if it becomes worse and there is a high chance it will happen," said a refinery official with direct knowledge of the matter.

Singapore's Wilmar International and Malaysia's KL Kepong and Kwantas Corp own the refineries and have been slowing operations following a curfew imposed by authorities last week after Filipino gunmen attacked Malaysian security forces in Sabah.

Company officials declined to comment.

Sabah is Malaysia's top oil palm growing region, accounting for a quarter of national production. Much of the palm oil from Sabah is shipped to China -- the world's second largest consumer of edible oils.