Moscow ? One of Russian President Vladimir Putin’s most prominent adversaries, jailed ex-oil magnate Mikhail B. Khodorkovsky, suffered a facial wound when another inmate slashed him with a knife, his attorneys said Saturday.

One of the lawyers, Yury Schmidt, told Knight Ridder Newspapers that he didn’t believe the attack was an attempt to kill Khodorkovsky, who he said was in good condition in the Krasnokamensk prison near the Siberian city of Chita, more than 3,000 miles east of Moscow.

In a statement on Khodorkovsky’s Web site, however, Schmidt repeated allegations that his client’s life is in danger and suggested that the government is to blame.

Khodorkovsky is serving an eight-year sentence for fraud and tax evasion after a May 2005 conviction that his supporters called Kremlin retribution for defying Putin.

Khodorkovsky was once Russia’s richest man, with a $15 billion fortune. But Forbes magazine recently put his net worth at $500 million, after the government renationalized the most valuable parts of Yukos, which was Russia’s largest private oil firm.

Last week, the Moscow City Court upheld a lower court’s March 16 order to freeze $6 million in assets controlled by Open Russia Foundation, a charity started by Khodorkovsky.

The government said the action was part of its tax-fraud investigation of Yukos and former top Yukos officials.

“All attempts by Khodorkovsky’s lawyers to place all the responsibility (on prison officials) are absurd,” federal prisons spokesman Alexander Sidorov said, according to Russian news media.

He blamed the incident on a quarrel between the two inmates.

Natalia Terekhova, another Khodorkovsky attorney, told Echo Moscow radio that a 23-year-old cellmate with mental problems was responsible.