Mikhail Beketov, a newspaper editor and environmental activist in the Moscow suburb of Khimki who was brutally assaulted last week, has been transferred to a Moscow hospital for treatment and for his own safety after a series of threatening phone calls, colleagues said Monday.

Beketov, editor and owner of Khimkinskaya Pravda, a weekly in the town on Moscow's northern outskirts, was discovered Thursday bloodied and unconscious near his home after an attack that his friends say is linked to his criticism of local authorities' deforestation plans.

He was transferred over the weekend from a Khimki hospital to Moscow's Sklifosovsky clinic, where he remained in a coma Monday, said Ludmila Fedosova, an environmental activist who had worked with Beketov on anti-deforestation initiatives.

Beketov told friends and colleagues that he had been receiving threats in the weeks and months before last week's attack, and Fedosova said Monday that he was transferred in part because of menacing phone calls to Khimki's Hospital No. 1, where he was being treated.

"He is still in a coma, but he was receiving telephone threats even as he was being operated on," Fedosova said.

The callers said they would eventually kill Beketov, Yabloko leader Sergei Mitrokhin said Monday, citing conversations with the doctors who received the calls.

The move to the Sklifosovsky clinic was also necessitated by a lack of sophisticated medical equipment at the Khimki hospital, Fedosova said.

Beketov had his leg amputated, but a necessary skull operation has been delayed because of his critical condition, Mitrokhin said.

Khimki police said last week that they had opened a criminal investigation into the attack.

Oleg Mitvol, the outspoken and embattled deputy head of the Federal Inspection Service for Natural Resources Use, said Monday that he had asked President Dmitry Medvedev to "take [the Beketov] situation under his personal control," Interfax reported.