DETROIT (AP) — Subaru plans to expand its Indiana factory and add workers to build the Impreza small car there in 2016, a person briefed on the matter says.

The person spoke on the condition of anonymity because the announcement is scheduled to be made Wednesday in Japan.

Currently the factory in Lafayette, Indiana, employs around 3,600 and builds the Legacy and Outback cars and the Tribeca SUV. It also builds the Camry midsize car under contract with Toyota.

The person says hundreds of jobs will be added but the exact number was unknown. The person didn't know how much money would be invested in the factory.

Subaru's U.S. sales have doubled in the past five years and are up 17 percent through April. Last year the automaker sold more than 336,000 cars and trucks, a 26 percent increase. That's double the growth rate for the entire U.S. auto market.

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.