Porsche has stopped deliveries of the most expensive version of its overhauled 911 sports car after two of them caught fire, the German automaker said.

Engineers at Porsche's Stuttgart-based headquarters are examining the remains of the gutted vehicles used in Switzerland and Italy to determine the cause of the fires, a spokesman said on Tuesday, confirming a report on German newswire dpa.

The Volkswagen-owned carmaker expects to conclude the investigation this week, the spokesman said, adding that Porsche had this year delivered 322 of the GT3 models, which start at 137,000 euros ($187,700).

Porsche expects to hit a target of selling more than 200,000 sports cars and SUVs in 2015, three years earlier than first scheduled, chief executive officer Matthias Mueller said last week. - Reuters