One of Tokyo's major subway lines was briefly shut down at the peak of the evening rush hour after suspicious white powder was found in a station.

In the wake of the anthrax outbreak in the United States, nerves have been frayed in Japan after a series of scares involving white powder. Most of the incidents are believed to have been pranks.

"I wish they would stop playing these hoaxes, it scares everyone. They say that terrorism is really a play on the mind," one passenger said as he left the station.

In March 1995, Tokyo's subways were the site of a sarin gas attack by a doomsday cult, which released the lethal gas on several subway lines including Hibiya. Twelve died and nearly 6,000 became sick in that attack.

According a police spokesman the unidentified white powder that was found on Thursday was discovered in the Higashi-Ginza station on the Hibiya subway shortly after 6:00 p.m.

The lines were re-opened less than an hour later after police removed the substance from a public toilet. Witness said the loudspeaker at each station on the line had informed passengers that a suspicious powder had been found, but no evacuations were made.