Human rights group Amnesty International was evicted from its office in Moscow on Wednesday morning by city authorities.
Staffers told Reuters they arrived at work to find the locks changed, alarm systems removed, the electricity system cut off, and official seals placed over the office entrances declaring employees could not enter the building without a city official.
Amnesty's Europe and Central Asia director, John Dalhuisen, called the incident "an unwelcome surprise for which we received no prior warning." The group has been critical of the Kremlin's human rights violations, particularly through its bombing campaign in Syria.
The Moscow city government said that Amnesty's lease had expired after the group ignored a debt notice, but Amnesty claimed it had documents to prove that all necessary payments had been completed.
The organization has rented the office from Moscow's department of city property for 20 years. An Amnesty employee told Reuters that the group had always completed its payments on time.
"Given the current climate for civil society work in Russia, there are clearly any number of plausible explanations, but it's too early to draw any conclusions," Dalhuisen said in a statement. "We are working to resolve the situation as swiftly as possible and very much hope there is a simple administrative explanation for this setback to our work."