A 13-year-old boy who lives in Italy with his adoptive parents took his father's Mercedes and drove more than 800 km (500 miles) through Europe in an apparent attempt to reach his birth family in Poland, Italian police said on Saturday.

He set off on Thursday afternoon from the small town of Pederobba in northern Italy with 200 euros in his pocket and drove the high-powered automatic car for almost 24 hours before being stopped by German police on a motorway near Leipzig.

"The boy's sister and natural parents are in Poland and it seems he was going there to meet his sister"

"The boy's sister and natural parents are in Poland and it seems he was going there to meet his sister," said an Italian police spokeswoman.

Media reports said the boy had an argument on Thursday afternoon with his adoptive mother.

"The boy has told his parents he is sorry and has recognised he was in the wrong," the police spokeswoman said, adding that he was on his way back to Italy.

According to newspaper reports the boy loved cars and was an expert go-kart driver.