Colonies of giant biting spiders have attacked villagers and sparked panic in remote north-east India.
But officials said locals’ attempts to treat the painful swelling caused by the bites may be more dangerous than the spiders themselves.
Two bite victims have died in Tinsukia district.
Officials said it is unclear whether they died from venom or from treatment by witch doctors who cut them with razor blades to drain the wounds.
No postmortem examinations were carried out before the victims were cremated.
Doctors at Sadiya town hospital said another seven victims were given antibiotics after they tried to drain their wounds.
Ecologist LR Saikia, from Assam’s Dibrugarh University, said the hairy spiders may be a newly discovered tarantula species.
The hairy spiders were first noticed about a month ago across Tinsukia district’s grassy plains and dense jungle forests north of the Brahmaputra River.
Ecologist Mr Saikia said: “It looks like a new species. We haven’t been able to identify it.”
Officials cannot use anti-venom in treating bite victims until the species is identified.
Meanwhile, villagers are keeping lamps on at night and standing guard against spiders entering their mud-and-thatch huts.
About 100,000 villagers, mostly poor rice farmers, live in the area which is cut off from roads by the river.
Officials said the spiders are now also showing up south of the Brahmaputra.
AP