Taiwanese prosecutors on Thursday accused a group of 22 men of felling several 2,000-year-old trees in the worst case of illegal logging in the island's history.

Prosecutors in the northeastern Ilan county sought a 15-year jail term and a fine of Tw$3.85 million ($128,500) for the 43-year-old Ho Chen-fa, the leader of the group, and jail terms of up to 10 years for the rest of the group.

The defendants were also accused of illegally possessing firearms, which had been used against official mountain rangers, according to prosecutors.

"This criminal group has shown no (respect for) the valuable 'divine' trees and sometimes they cut down the whole trees only for a small part of them," the prosecutors said in an indictment paper.

Very old trees are revered in Taiwan and referred to as 'divine'.

The prosecutors' investigation found that the group had poached more than 40 cedars, several of them aged more than 2,000 years, from February to April this year.

Police arrested the group in April, discovering tree products worth around Tw$10 million.

The case sparked public outrage and prompted Premier Sean Chen to push for a severe crackdown on the crime.