PERM, Russia (AP) _ Russian passengers who returned from a shopping trip to India refused to leave their plane after officials ordered tests to detect the presence of plague, a news agency reported today.

Many of those who arrived Monday night in Perm, a large industrial city 750 miles east of Moscow, were worried their purchases would be destroyed if plague were found, ITAR-Tass said. Despite pleas from authorities, they stayed inside the jet without food or heat.

A pneumonic plague outbreak began in late September in the western Indian city of Surat and has since spread to other areas of the country. At least 61 people have died; unofficial estimates put the death toll at 300.

Russian authorities, already grappling with cholera and diphtheria epidemics, have restricted travel to India and imposed a six-day quarantine on people arriving from there.

Officials did not say how many passengers were aboard the plane that landed in Perm. The crew left the plane immediately after landing and underwent tests for the plague, ITAR-Tass said.