The second season of the documentary series The Tokyo Trials premiered on International Channel Shanghai on Tuesday.

To mark 70 years since the commencement of the post-World War II tribunal against 28 military and political leaders of Japan, the Shanghai Media Group News Center produced the documentary with the Tokyo Trial Research Center at Shanghai Jiao Tong University.

Earlier this month, the first season of the documentary, which was produced by the same team and aired last year, was named "Best Documentary Series" at the Asian Television Awards in Singapore.

The second season's three episodes were made because of stronger research and new discoveries, said Song Jiongming, head of the SMG News Center.

In addition, current developments in international politics have inspired the documentary makers to see the historical event with a more objective and accurate point of view, he said.

The three new episodes - The Battle for the Truth, Beyond Victor's Justice, and A History Etched in Memory, highlight new historical discoveries and academic achievements, including video of trial testimony and evidence disclosed for the first time. Newly discovered video footage also shows witnesses speaking in court.

Cheng Zhaoqi, a professor of history at Shanghai Jiao Tong University, said new evidence shows that the Japanese defendants repeatedly committed perjury during the trial.

The trials, known as the International Military Tribunal for the Far East, was held in Tokyo from May 1946 to Sept 1948. The Japanese leaders were tried on charges of conspiring to start and wage war, for committing atrocities against humanity and for planning, authorizing or failing to prevent transgressions among military commanders.

All of the defendants were found guilty and seven were sentenced to death.

A number of Japanese politicians, such as former prime ministers Naoto Kan and Yukio Hatoyama, and former Japanese ambassador to China Yuji Miyamoto, were interviewed for the documentary and spoke about their perceptions of the trials.

The three new episodes also show the site of the trials and Sugamo Prison, where the defendants were held. No traces of these places remain, the documentary's makers found.