A court in Libya has adjourned the trial of six Bulgarian medics and nine Arabs accused of deliberately infecting nearly 400 Libyan children with the HIV virus.

A lawyer acting for the Bulgarians said he had had insufficient time to examine 1,600 pages of prosecution material.

The trial first began in February, but was postponed at the request of the defence.

This is a highly unusual case. The medics were arrested more than a year ago during an investigation into an outbreak of Aids in a children's hospital in Benghazi.

Nineteen Bulgarians were detained at the time, along with other foreign and local workers. Most were later released, but the six Bulgarians, as well as eight Libyans and a Palestinian, were charged with intentionally infecting 393 children with the virus that cuases Aids.

The Libyans say more than 20 of them have now died.

If convicted of their murder, the defendants could face the death penalty.

Bulgaria has repeatedly said it does not believe its medics are guilty, and has called for a fair trial.

A Bulgarian diplomat in the region told the BBC it was out of the question that the Bulgarians could have acted deliberately, but said it was possible they had been negligent in some way.

But he said there were many puzzling aspects to the case.

Libya and Bulgaria have traditionally had good ties.

Several thousand Bulgarians work in Libya - mostly as doctors and engineers. This trial has put a strain on relations.