Updated

Two workers were killed and two others were in critical condition in a Haifa hospital late Sunday after inhaling poisonous material from an accidental leak at the country's oil refinery, the rescue service said.

The rescue service said in a statement that its crews worked to resuscitate the victims at the scene and on the way to the hospital. Paramedic Eli Geller said the four were not breathing and had no pulse when they were found. He told Israel Radio, "One's pulse has been restored, and a second is showing signs of recovery."

The rescue service said in a statement that two of the men died in the hospital.

Eight other people — five workers and three members of the rescue team — were also affected, but not seriously, the statement said.

Israel Radio said the leak was contained within the refinery, and there was no danger outside.

Firefighter Pini Seeson told Israel Radio from the scene that a worker collapsed while replacing a seal because of the leak, and his partner was also overcome while trying to get him out. The two were wearing protective gear, he said, but two others who went in unprotected to extract them were poisoned.

The huge oil refinery is on Haifa's Mediterranean seacoast. Haifa, a key seaport, is Israel's third largest city with a population of 265,000.

The refinery has been a target of environmentalists and worried residents because of the potential for widespread damage and casualties in the Haifa area in the event of an accident or an attack.

During a 34-day war with Lebanese Hezbollah guerrillas in 2006, a Katyusha rocket fired from south Lebanon hit an open area in the facility, causing minor damage, according to the refinery company.