For details about the arrest, please see the link below to HRW
An EU spokesperson on 19 March stated:
“We believe that the sentencing of Oyub Titiev is directly connected to his human rights work for Memorial, an organisation that has been the subject of ongoing intimidation and harassment in the North Caucasus and beyond. We also believe that Mr Titiev has not received a fair trial. His sentencing continues a trend of arrests, attacks and discrediting of human rights defenders and journalists who work in that region of the Russian Federation. Mr Titiev’s predecessor as head of Memorial in Chechnya, Ms Natalia Estemirova, was killed in 2009 and, almost ten years later, not a single person has yet been brought to justice for this crime,”.
“The European Union expects Mr Titiev to be released immediately and unconditionally. The Russian Federation freely entered into commitments, first in Helsinki in 1975 and later in Copenhagen in 1990, to ensure “the right of everyone, individually or in association with others, to seek, receive and impart freely views and information on human rights and fundamental freedoms, including the rights to disseminate and publish such views and information.” We expect these commitments to be upheld”.
https://www.hrw.org/news/2019/03/18/russia-rights-defender-sentenced-four-year-prison-term
https://www.europeaninterest.eu/article/european-union-expects-oyub-titiev-released-immediately/