TOKYO - Subaru said Wednesday that it was investing $400 million to expand its Indiana factory and would add 900 workers to build the Impreza small car there in 2016.

The plant now employs about 3,600 people and builds the Legacy and Outback cars and the Tribeca SUV. It also builds the Camry midsize car under contract with Toyota Motor Corp., the top shareholder in Subaru with a 16.5 percent stake.

Subaru, part of Fuji Heavy Industries Ltd., said it would boost capacity at one of two assembly lines at the Lafayette plant - now being used to build the Camry - from 100,000 vehicles to 200,000.

It had already announced it would boost production capacity at the other line from the current 170,000 vehicles to 200,000.

Production of the Impreza is expected to start by the end of 2016, Subaru spokesman Yoshiaki Tabei said.

Subaru sold 724,500 vehicles globally for the fiscal year that ended in March, up 13 percent from the previous year, with 357,600 sold in this country. It sold 163,100 vehicles in Japan.

Subaru's U.S. sales have doubled in the last five years. Subaru of America Inc., the company's U.S. arm, is based in Cherry Hill.

U.S. sales of the Impreza, now built in Gunma, Japan, have fallen 31 percent this year, due largely to a shortage of vehicles on dealer lots. Ward's Automotive says Subaru has only enough Imprezas on the ground to supply dealers for 29 days. A 60-day supply is considered optimal.