Panicked villagers in a remote Indian state complained Monday of an invasion of giant venomous spiders that resemble tarantulas but are unknown to local specialists.

Indian media said that a dozen people had been bitten and treated in hospital, with two unconfirmed deaths reported.

"Initially we thought it was a prank, but later on we saw swarms of this peculiar kind of spider biting people," Ranjit Das, a community elder in the town of Sadiya in the northeastern state of Assam, told AFP by telephone.

Authorities have swung into action by fogging and spraying insecticides in the area, 600 kilometres (370 miles) east of Assam's main city of Guwahati, and a team of scientists have been dispatched to investigate.

"We visited the spot and found it akin to the tarantula, but we are still not sure what this particular species is," said L.R. Saikia, a scientist from the department of life science of Dibrugarh University in Assam.

"It appears to be an aggressive spider with its fangs more powerful than the normal variety of house spiders," he told AFP.

Specimens have been sent outside Assam for identification by arachnologists, he said.