The details were published in a London-based magazine, Foreign Report.

The magazine said that in one of the accidents, the Israeli authorities came close to ordering the evacuation of homes near the Israel Institute for Biological Research in Nes Ziona, a suburb of Tel Aviv.

But in separate statements today, the institute and the office of the Prime Minister, Binyamin Netanyahu, said there had never been any accidents at the site which resulted in death or injury.

"No person has ever been killed in a work accident at the Biological Institute since its inception 45 years ago," said a statement issued by Mr Netanyayu's spokesman.

"No incidents which have caused harm or could cause harm have ever occurred at the institute," it said.

Former director jailed

The Foreign Report magazine said the facility made biological and chemical weapons.

Last year, Israel's Haaretz daily reported that the institute was developing antidotes to various types of nerve gas, including the deadly VX.

A former director of the institute, Marcus Klingberg, was sentenced to 18 years in prison in 1983 for reportedly passing secrets about biological warfare to the Soviet Union.

The trial was held in secret and not made public until 1993.

Authorities have refused repeated requests to free Mr Klingberg, now 80 and seriously ill, arguing that he still possesses potentially damaging information about the work of the institute which should not be made public.