Illegal online trade in furs and specimens of endangered animal and plant species has been rampant, prompting police and related authorities to bolster their countermeasures.

The police have acted on 23 cases since last year, but this is believed to be only the tip of the iceberg.

A tiger pelt placed on a major Internet auction site in August carried such phrases as "rare" and "difficult to obtain." The item had no official certificate, as required by law.

According to the Environment Ministry, trade in species designated as endangered by the Washington Convention was basically banned in Japan — unless the seller obtains an official certificate. This exception took effect in June 2014.

According to Life Investigation Agency, a Nagano-based nongovernmental watchdog on illegal trade of endangered species, there are more than 50 cases of shady trade every year.

Against this backdrop, the National Police Agency has started to take action. In February, the police turned over to prosecutors their case against a man in Miyoshi, Tokushima Prefecture, for auctioning off a dead mountain hawk eagle.

The NPA tackled 23 cases between January 2014 and June this year, with 16 of the illicit trades detected on the Internet, the police said.

Yahoo Auctions, a major Internet site, said it is cooperating with the authorities by deleting problematic items if they fail to fulfill legal requirements.