Polar bears halt Arctic research in north Russia
Pictures show how polar bears have besieged a team of Arctic meteorologists working in a remote corner of Russia.
The team has been unable to take daily sea readings after fights broke out over food between the bears who settled near the Fyodorov weather station, on Vaygach island in Russia's far north.
The team failed to scare the bears off with flares and have no other weapons.
The Russian government has pledged help, the WWF conservation group says.
Polar bears in Russia live all along the Arctic coast from Murmansk in the west to Chukotka in the east.
Scientists have observed a gradual rise in bear attacks on humans in recent years.