Six foreign health workers jailed in Libya for years on charges of deliberately infecting children with the AIDS virus were convicted and sentenced to death in a case that has long sparked international outrage and did so again Tuesday.

The United States and Europe had called for the release of the five Bulgarian nurses and Palestinian doctor, warning Libya that the ruling would affect relations. Already the long trial has held up efforts by Libyan leader Moammar Gadhafi to repair his rogue image and rebuild ties with the West.

The nurses and doctor have been in jail since 1999 on charges that they spread the HIV virus to more than 400 children at a hospital in the Libyan city of Benghazi during a botched experiment to find a cure for the disease. Western nations blame the infections on unsanitary conditions at Libyan hospitals and accuse Tripoli of using the six health workers as scapegoats.

Bulgaria and the EU swiftly condemned the decision, and chief Bulgarian counsel Trayan Markovski said the defendants would appeal to the Libyan Supreme Court.

"Sentencing innocent people to death is an attempt to cover up the real culprits and the real reasons for the AIDS outbreak in Benghazi," said Bulgarian parliamentary speaker Georgi Pirinski.

EU spokesman Johannes Laitenberger said there was no immediate decision on EU action against Libya but said he "did not rule anything out."

Presiding Judge Mahmoud Hawissa took just seven minutes to confirm the presence of the accused — who all answered "yes" in Arabic — and read the judgement in the longest and most politicized court process in modern Libyan history.

The five Bulgarians and the Palestinian did not react. But the father of an infected child, yelled "God is great!" and "Long live the Libyan judiciary!"

Detained for nearly seven years, the defendants had previously been convicted and condemned to death, but Libyan judges granted them a retrial last year after international protests over the fairness of the proceedings.

An international legal observer, Francois Cantier of Lawyers Without Borders, promptly criticized the retrial as lacking scientific rigor. Research published this month said samples from the infected children showed their viruses were contracted before the six defendants started working at the hospital in question.

"We need scientific evidence. It is a medical issue, not only a judicial one," Cantier said after the verdict. His colleague, Ivan Paneff, said Lawyers Without Borders had tried to persuade the judges to commission international experts to investigate conditions at the hospital but "they refused."

Bulgaria's Pirinski made the same point in Sofia, saying: "The court has not taken into account the unquestionable judicial and scientific evidences for the innocence of the medics."

Libyans strongly supported a conviction. Some 50 relatives of the infected children — about 50 of whom have already died of AIDS — waited outside the court early Tuesday morning, holding poster-sized pictures of their children and bearing placards that read "Death for the children killers" and "HIV made in Bulgaria."

After the verdict, relatives at the court gates chanted "Execution! Execution!"

In Bulgaria, hundreds of people had staged peaceful protests in support of the five nurses on Monday.

Luc Montagnier — the French doctor who co-discovered HIV — testified in the first trial that the virus was active in the hospital before the Bulgarian nurses began their contracts there in 1998.

More evidence for that argument surfaced on Dec. 6 — too late to be submitted in court — when Nature magazine published an analysis of HIV and hepatitis virus samples from the children.

Using changes in the genetic information of HIV over time as a "molecular clock," the analysts concluded that the virus was contracted before the six defendants arrived at the hospital — perhaps e0ven three years before.

Idriss Lagha, the president of a group representing the victims, rejected the Nature article, telling a news conference in London on Monday that the nurses had infected the children with a "genetically engineered" virus. He accused them as doing so for research on behalf of foreign intelligence agencies.

In testimony last month, the defendants denied intentionally infecting children.

"No doctor or nurse would dare commit such a dreadful crime," said nurse Cristiana Valcheva, adding that she sympathized with the victims and their families.

A second Bulgarian, Valentina Siropulo, testified that of her seven years in Libya, "I've spent only 6 months working as a nurse and the rest of the time in prison."

Gadhafi, who has been trying to refashion his image from leader of a rogue state, got his government to ask Bulgaria to pay compensation to the children's families.

But Sofia rejected the idea as indicating an admission of the nurses' guilt.