A suspect in the brazen daytime theft of two Edward Munch (search) masterpieces was being questioned over the weekend, and police said they were hopeful more arrests would follow.

The 37-year-old man, who has not been identified, was arrested Friday in Oslo. He is suspected of involvement in the raid of the Munch Museum (search) in Oslo in August, where three armed and masked robbers escaped with "The Scream" (search) and "Madonna."

Police prosecutor Morten Hojem Ervik declined to say how the man might have been involved, but the Norwegian newspaper Verdens Gang reported that police believe the suspect supplied the getaway car.

"Is this a breakthrough? As long as (the paintings) are still out there, you can debate whether it's a breakthrough or not," Hojem Ervik said. "But at least it brings the investigation one step further."

The paintings, which are among Munch's best-known, were stolen on Aug. 22. "The Scream," a 20th-century icon that depicts an anguished figure who appears to be screaming or shielding his ears from a scream, is too well known for the thieves to try to sell, experts say.