Relatives of Sasa Cvjetan were at the court to hear his sentence

Sasa Cvjetan, 29, was a former member of a special police unit called the Scorpions.

Most of the victims of the massacre, in the town of Podujevo, in March 1999, were women and children.

The trial attracted world attention as it is unusual for Serb courts to try Serbs in war crimes cases.

Last July five Kosovo Albanian children who survived the incident and have been living in Britain were flown to the Serbian capital to testify.

'Monstrous crime'

Eighteen-year-old Saranda Bogujevci told the court in Belgrade how soldiers and police gunned down her brothers, mother, grandmother, aunt and cousins.

Judge Biljana Sinanovic said Cvjetan had committed "a really monstrous crime and the court has decided on the highest penalty".

Serbia has been anxious to show itself capable of trying war crimes cases at home, and opened a special war crimes court last year.

The United Nations war crimes tribunal, which many Serbs see as biased against them, has agreed to pass on lower-level cases but insists on trying higher-level offenders in The Hague.

Cvjetan denied the charges against him, saying he "never fired on civilians and children".

He claimed he was a scapegoat of the government which wanted to make a show of dealing with war crimes while protecting the real culprits.

Investigators say several other unnamed men are believed to have taken part in the killing, along with Cvjetan and another suspect, Dejan Demirovic, who has not been caught.