Prominent opposition politician Boris Nemtsov did not turn to police over murder threats, a source with law enforcement agencies told Interfax.

A check revealed that Nemtsov sent no appliation to police over murder threats that he had recieved, the source said.

Nemtsov may have recieved threats related to jealousy, he said.

Vadim Prokhorov, a lawyer for Nemtsov's family, said earlier on Saturday that Nemtsov had recieved murder threats several months ago. "Several months before today threat were made on social networks. We filed an application [with police] but there was no reaction," Prokhorov told Interfax.

Nemtsov was killed in downtown Moscow in the early hours on Saturday.