Georgiy Gongadze exposed high-level corruption
A former Ukrainian general suspected of carrying out the high-profile murder of journalist Georgiy Gongadze has reportedly confessed to the killing.
A senior police official said Oleksiy Pukach had also implicated senior political figures in the murder.
Mr Gongadze's decapitated body was found in a forest in September 2000.
Three others - all former policemen - were jailed for the murder last year but Gen Pukach remained on the run until his capture on Tuesday.
Mr Gongadze was an investigative journalist who had exposed high-level corruption.
He was abducted in 2000 and his body was found months later. He had been beaten and strangled, his body doused in petrol and burned.
Prosecutors allege that Gen Pukach - who was detained near the capital, Kiev - organised the abduction and personally strangled Mr Gongadze.
Gen Pukach was the chief of the interior ministry's surveillance department at the time of the killing.
Three others were jailed for the murder last year.
Mykola Protasov was given a sentence of 13 years, while Valeriy Kostenko and Oleksandr Popovych were each handed 12-year terms.
But Mr Gongadze's family has always claimed someone more senior was behind the killing.
His widow, Myroslava, told the BBC's Europe Today programme: "For me and Ukraine it's a very important step in bringing justice to my husband... and generally to society. It's a cleansing process.
"He knows the name of people who ordered the crime," she went on.
"The thing is, it's easy to mention names, but it's not that easy to collect all the evidence to present in court against instigators and organisers."
Secret tape recordings released soon after the killing appeared to implicate the then-President, Leonid Kuchma.
In the recordings - made secretly by a member of his personal guard and then released by an opposition politician - Mr Kuchma allegedly discussed ways of removing the journalist, with a former interior minister, Yuri Kravchenko.
The latter was later found dead and was said to have committed suicide.
Mr Kuchma did not deny the voice in the recordings was his, but insisted it was doctored to make him appear to say things he did not actually say.
The scandal prompted massive street protests against Mr Kuchma's government.