ROME (Reuters) - The death toll of Italian veterans of Balkan peacekeeping missions linked to the so-called ``Balkans syndrome'' has risen to five, Italian newspapers reported on Saturday.

All five veterans died from cancer.

Italian newspapers said Italy's military prosecutor was investigating some 20 cases which the media have linked to the ''Balkans syndrome.''

Press reports have suggested the illnesses could be linked to depleted uranium shells used by Nato during its 1999 campaign to oust Serb forces from Kosovo.

Official reaction has been to deny that such a link exists, but on Friday Belgium called for European Union defense ministers to discuss health problems suffered by peacekeepers in former Yugoslavia.

The call by Belgian Defense Minister Andre Flahaut came amid rising concern in Europe over mysterious illnesses among Balkan peacekeeping veterans.

In Lisbon, the Diario de Noticias newspaper reported that Portugal had ordered medical tests for its soldiers serving in Kosovo to check for radiation from depleted uranium ammunition used in the NATO campaign.

Concerns over possible health effects of depleted uranium shells in Kosovo have also been raised by service members or civilian aid workers in Britain and the Netherlands.

U.S. attack jets fired some 31,000 rounds of depleted uranium ammunition -- used to pierce armor -- at Serbian tanks and armored cars during the Kosovo campaign, according to a United Nations expert.

The Pentagon said in March that the remains of the shells did not present a significant health hazard.