TOKYO (Reuters) -Renesas Electronics Corp now believes damage from a fire at its chip-making plant was more extensive than first thought, the Nikkei daily newspaper reported on Monday. The company had initially said 11 machines were damaged, but the Nikkei reported that the number of inoperable machines was now believed to be around 17. A company spokeswoman would not confirm a specific number. A Renesas-owned chip plant in northeast Japan was hit by fire earlier this month. The company has said it will take at least a month to resume production at its 300mm wafer line, but replacing damaged machines could take several months. An extended outage could add to a global shortages of chips which is disrupting some production of cars and electronic devices. The company accounts for 30% of the global market for microcontroller units used in cars, and two-thirds of the chips produced at the facility are for the auto industry.