Four suspected poachers have been arrested for killing a critically endangered Sumatran tiger, Indonesian police said Monday, highlighting the Southeast Asian nation's battle with illegal wildlife trafficking.

Authorities in Aceh, at the northern tip of Sumatra island, said they were also searching for a fifth suspect, all allegedly part of a crime syndicate.

At a press briefing Monday, police displayed a confiscated tiger skin along with teeth and bones taken from the suspected traffickers.

The men -- who had been under police surveillance -- also had the teeth and bones of a sun bear, authorities added.

"The four ensnared this protected animal in a trap and it was left to die," said Aceh police spokesman Margiyanta, who like many Indonesians goes by one name.

Police displayed a confiscated tiger skin along with teeth and bones taken from the suspected traffickers
Police displayed a confiscated tiger skin along with teeth and bones taken from the suspected traffickers AFP / Muhammad AZKA

We think "the perpetrators are part of a syndicate given the professional way they caught the animals".

The animal parts may have been destined for buyers outside the region, he added.

In January, Aceh police arrested a man trying to sell a tiger skin for some 90 million rupiah ($6,400), and dozens of wildlife crime cases have been recorded in recent years, according to the region's conservation officials.

Poaching accounts for almost 80 percent of Sumatran tiger deaths, according to TRAFFIC, a global wildlife trade monitoring network.

Sumatran tigers are considered critically endangered by protection group the International Union for Conservation of Nature, with fewer than 400 believed to remain in the wild.