ATHENS — The Greek police arrested and then quickly released the owner and editor of a respected investigative magazine on Sunday morning hours after he published a list of more than 2,000 Greeks who were said to have accounts at a bank in Switzerland, throwing new controversy into a scandal over whether the government is actively pursuing suspected tax cheats.

The dramatic moves, which tens of thousands of Greeks were following on the Internet, came days before Greece’s European partners were to meet to decide whether to grant tens of billions of euros in new aid to the financially struggling nation. Greece’s lenders have long said that the government must crack down on tax evasion to be eligible for more aid.

The police said they had been ordered to take the editor, Kostas Vaxevanis, who runs Hot Doc magazine and who is one of the nation’s most famous investigative journalists, into custody on misdemeanor charges. The Greek news media reported that the charges concerned the violation of the privacy of those on the list.

Mr. Vaxevanis posted a message to his Twitter account early Sunday saying that 15 officers had surrounded the home of a friend with whom he had been staying “like Greek storm troopers in German uniforms.”