Police spokesman Bernhard Schodrowski said five divers searched a lake near Anna Mikhalchuk's home, and more than 80 officers with sniffer dogs swept through nearby gardens and along train tracks over several hours. They failed to turn up any trace of her.
"This [search] was part of the regular criminal investigation," Schodrowski said. "The police start their search where they lose track of a missing person."
Schodrowski said efforts to find Mikhalchuk, 52, would continue.
Also known in Russia by the name Anna Alchuk, Mikhalchuk left her apartment on March 21 and has not been seen since. She moved to Berlin with her husband, Mikhail Ryklin, in November 2007.
In 2005, she was acquitted by a Moscow court on charges of inciting religious hatred for her works in a controversial art exhibit condemned by the Russian Orthodox Church.
The 2003 exhibit -- titled "Caution, Religion" -- was organized by the Sakharov Museum.
Ryklin sent a letter to Berlin police on Saturday, asking them to intensify the search for his wife.
The Berlin Tagesspiegel daily wrote that Mikhalchuk is Jewish and quoted Ryklin as writing that his wife had received several anonymous threats in the past. Ryklin teaches at Humboldt University.
A Message from The Moscow Times:
Dear readers,
We are facing unprecedented challenges. Russia's Prosecutor General's Office has designated The Moscow Times as an "undesirable" organization, criminalizing our work and putting our staff at risk of prosecution. This follows our earlier unjust labeling as a "foreign agent."
These actions are direct attempts to silence independent journalism in Russia. The authorities claim our work "discredits the decisions of the Russian leadership." We see things differently: we strive to provide accurate, unbiased reporting on Russia.
We, the journalists of The Moscow Times, refuse to be silenced. But to continue our work, we need your help.
Your support, no matter how small, makes a world of difference. If you can, please support us monthly starting from just $2. It's quick to set up, and every contribution makes a significant impact.
By supporting The Moscow Times, you're defending open, independent journalism in the face of repression. Thank you for standing with us.
Remind me later.