MOSCOW, June 6 (RIA Novosti) - Moscow police have detained several people suspected of involvement in a widely-publicized series of arson attacks on vehicles in the Russian capital, a police spokesperson said on Friday.

Over 20 cars have been set on fire in several residential areas of Moscow since the start of the month. Police said most of the cars set fire to were grey, and that several of them were expensive foreign cars, including a BMW and an Audi.

"During an investigation and with the help of Moscow residents we have detained several suspects believed to be responsible for setting cars on fire," Olga Chugunova said, without specifying any details.

"The names of the suspects will remain confidential for now in the interests of the investigation," she added.

Moscow police earlier circulated a reward of up to a million rubles (about $42,000) for information leading to the apprehension of the arsonist or arsonists.