Assertion: zodiac | /r/CapableOf | send a 13-character cipher
Facets:
value: on april
type: TEMPORAL
Source sentences:
text: On April 20 the Zodiac sent a letter to the Chronicle including a 13-character cipher, a diagram of a bomb he planned to use on a school bus, and a statement that he was not responsible for the February 18, 1970, bombing of a police station in San Francisco.