Tens of thousands of people joined a demonstration outside the Diet on Saturday, in a sign of growing public anger over cronyism scandals engulfing Prime Minister Shinzo Abe.

Organizers say about 50,000 people attended this weekend's rally in Tokyo — the biggest in nearly three years. Protesters, many young, held up signs calling Abe a "liar" and seeking his resignation.

The prime minister has been forced in the Diet to deny his involvement in two controversies over land deals to close associates. An alleged cover-up over the activity of Japanese troops during the Iraq War is also casting a cloud over his government. A spokesman for Abe's office didn't immediately respond to an email seeking comment.

The scandals have pushed Abe's approval ratings toward all-time lows, raising questions about his ability to win the ruling Liberal Democratic Party's leadership election in September. Victory would put him on track to become Japan's longest-serving prime minister.

"The large number of people gathering is due to growing anger," said Takeshi Suwahara, one of the leaders of Saturday's protest. "A strong sense of crisis is spreading — people now sincerely feel they have to speak out for what is right."

While the protests are significant in a country where people tend to be reluctant to attend public demonstrations, they are still dwarfed by rallies in the summer of 2015 over Abe's push to expand the powers of the Self-Defense Forces. Organizers of those gatherings said that around 350,000 people attended.

Helped by a divided opposition and a lack of strong challengers in his own party, Abe has so far been able to shake off several scandals and a slump in support stemming from the passing of controversial laws.