latch on to #2

マヤ終末論を信じ、とうとう小学校に乱入事件まで起きてしまいました。以前にも取り上げられていましたが（http://d.hatena.ne.jp/A30/20100623/1277286497）、ここのlatch on toとはどのような意味だったでしょうか。復習です。EnDoughくん、どうぞ。（UG）

China cracks down on 'Doomsday cult'

(CNN) -- Members of a fringe Christian group in China have been rounded up for spreading rumors of an impending apocalypse, pegged to the Mayan calendar.

Known as the "Almighty God" cult, the group latched on to the Mayan doomsday scenario to predict the sun will not shine and electricity will not work
for three days beginning on December 21, an official with the Department of Public Security in the northwest province of Qinghai told CNN.

Group members would spread doomsday rumors door-to-door or at public venues and claimed only they could save people's lives, according to authorities.

http://edition.cnn.com/2012/12/18/world/asia/china-doomsday-arrests/index.html?hpt=ias_c2