Japan on Thursday marked the 30th anniversary of the nerve gas attack on the Tokyo subway system by the AUM Shinrikyo doomsday cult, with the relatives of the victims striving to keep alive the memory of the worst terrorist attack on Japanese soil.

At Kasumigaseki Station in the Japanese capital, officials observed a moment of silence at around 8 a.m., the time when the deadly sarin nerve agent was released in train cars on March 20, 1995.

Shizue Takahashi, 78, who lost her husband, a deputy stationmaster at Kasumigaseki Station, in the attack, laid flowers at the site, and said, “It was a long 30 years. I don’t want people to forget about the incident.”