Rome/Paris  - Three western hostages who work for the international aid organization Doctors Without Borders have been set free, the Italian foreign minister said late Friday in Rome.

The government in Khartoum located the kidnappers despite their constant flight from one place to another, and negotiated with them to release the hostages.

Italian media reports said no ransom was paid.

A spokeswoman in Paris for the French-based Medecins Sans Frontieres (MSF,) as the organization is formally known, did not confirm the release.

In addition to the three Westerners - a Canadian nurse, an Italian physician and a French coordinator - a Sudanese hostage was also released.

The aid workers were kidnapped late Wednesday or early Thursday. They had worked in Serif Umra in the province of North Darfur for the Belgian section of MSF. (dpa)