"The plane has just landed. Depressurisation", Maris Gorodtsov, head of the Latvian civil aviation administration, said.
According to Gorodtsov, "the crew reported problems, in such cases there is a request to the nearest airport, the airport of the intended landing".
"All services were ready to receive the flight", he added.
The number of passengers on board is still unknown, as is whether there are any injured among them.
The plane, a Sukhoi Superjet 100 (SSJ100) with registration number RA-89041, was conducting flight AFL2101 from Riga to Moscow.
The SSJ100 is a twin-engine plane made by Russia's Sukhoi Civil Aircraft Company.