Photo/Illutration One of the smuggled perenties. This photo was taken on Nov. 26 at Tokyo's Marunouchi Police Station. (Nobufumi Yamada)

Six men are facing criminal charges on suspicion of smuggling two rare perentie lizards, a protected species under the Washington Convention, into Japan.

Tokyo police referred all six cases to prosecutors.

Two of the suspects, one of whom runs a pet shop dealing in exotic reptiles, were accused Nov. 26 of illegally importing the creatures in violation of the Customs Law and the Foreign Exchange and Foreign Trade Control Law.

Four others, some of them pet dealers, were also referred to prosecutors on suspicion of engaging in unauthorized trading and transporting crime-related items in violation of the Customs Law.

The perentie, a monitor lizard native to Australia, grows to 2 meters in length. The species is often referred to as "the most beautiful lizard in the world” by enthusiasts.

Police vowed to be on the lookout for similar cases due to the growing popularity of the reptiles.

According to police, a 36-year-old man who runs an online shop called Jewell that sells reptiles and other animals, tried to smuggle a perentie into Japan from Hong Kong without permission from the trade minister in January 2017. The other suspect, a 35-year-old man who is president of an animal trading company called Maple, is accused of doing the same in March last year.

One of the perenties was sold to a 38-year-old pet dealer, who then offloaded it to a 27-year-old male comedian for 6 million yen ($55,060).

A 41-year-old man who runs a pet shop purchased the other perentie from a 59-year-old pet dealer.

The four men are suspected of engaging in the unauthorized trading of perenties in the full knowledge that they were illegally smuggled into Japan.