By Daniel Leussink

TOKYO (Reuters) -Toyota Motor, the world's biggest automaker by sales, will extend until Wednesday a partial production halt at two domestic assembly plants due to an accident at a supplier's facility, a company spokesperson said.

The incident at supplier Chuo Spring, which makes engine and valve springs used in vehicles, also halted some production at group companies (NYSE:) Auto Body and Toyota Industries (OTC:).

The impacted lines would remain halted due to the incident, while a line at a plant of another group company, Gifu Auto Body, used for manufacturing of the Toyota Coaster minibus would also be stopped, the spokesperson said.

A spokesperson for Chuo Spring said an accident involving an explosion in a building at its Fujioka plant around 12:15 p.m. (0315 GMT) on Monday resulted in damage to the facility, adding that the police and the fire department were investigating.

Production in five lines at three Toyota Auto Body plants - all of the unit's lines - was stopped due to the accident, affecting production of minivans such as the Alphard as well as some Land Cruiser models, including for overseas markets.

The halted Toyota lines are at the automaker's Takaoka and Tsutsumi plants, both in Toyota City in central Japan which is also home to its headquarters.

Operations at all 14 of Toyota's domestic assembly plants ground to a halt in August due to a system malfunction.

Shares of Toyota on Tuesday closed up 0.8% at 2,681 yen, in line with broader market gains.