MOSCOW — The main suspect in Russian opposition politician Boris Nemtsov’s killing has signs of torture on his body and was forced to confess to the shooting, a human rights activist said Wednesday.

Investigators didn’t confirm or deny the accusations made by Andrei Babushkin, a member of a Russian human rights commission. But they said Babushkin may have broken the law by making the comments.

Babushkin told The Associated Press that he visited the detention center where main suspect Zaur Dadaev had been held on Tuesday.

Babushkin said there were abrasions on Dadaev’s body and that he had been “tortured by those who detained him” and later taken to the Investigative Committee, where “he was forced to confess.”

Five people have been detained in connection with Nemtsov’s shooting on Feb. 27. Dadaev was the only one who, according to a judge, confessed to the killing, though in court he didn’t admit guilt.

The commission that Babushkin belongs to is an unofficial advisory body to the president.

It operates under the auspices of the Kremlin, but many of its members are respected activists with decades-long careers in human rights work in Russia.

Russia’s Investigative Committee said in a statement that Babushkin and a journalist accompanying him had been allowed to visit Dadaev’s prison cell only to see the conditions under which he was being held, but had broken the law by publicizing details about the case.

“Such actions may be regarded as interference in the investigation,” the statement said.