The leader of a radical leftist group who spent the past five decades or so in hiding has deemed the novel coronavirus pandemic the right time to call for a communist revolution.

Takeo Shimizu, 83, the leader of the Chukaku-ha (middle core faction), resurfaced in public last September for the first time in about half a century.

He held a news conference in Tokyo on Jan. 27 where he sharply criticized the government’s handling of the COVID-19 health scare, claiming the coronavirus crisis has made Japan ripe for revolt.

“The circumstances for a revolution have arrived,” Shimizu said. “I want to call out to the working class.”

Decades ago, the Chukaku-ha repeatedly carried out terrorist acts in Japan, attempting to bring about a communist state. The group has long opposed the imperial system, which has been its main point of contention.

According to the National Police Agency (NPA), it was involved in the 1971 riots in Tokyo’s Shibuya district that left many people dead or injured. It later was involved in a brutal battle with a splinter group.

In 1990, the group launched a projectile into the grounds of the Kyoto Imperial Palace, one of the 124 guerilla acts police have attributed to it.

Shimizu went underground for about 50 years until he appeared at a meeting last fall. He did not go into detail about how he managed to survive while in hiding, only saying, “I was supported by many people.”

In recent years, Chukaku-ha has come out in opposition to U.S. military bases in Japan as well as nuclear power plants. In 1991, it declared that it would no longer engage in armed conflict, but police remain cautious about its group members.

The NPA said it had about 4,700 members as of the end of 2020.