The Zodiac serial killer delivered four ciphers to police daring them to discover him; one was solved immediately, the other not until 2020.

After millions of attempts, thousands of bad solutions and 51 years, the Zodiac Killer’s most infamous cipher has been solved.

Sam Blake, an Australian mathematician, first learned of the Zodiac Killer’s unsolved ciphers — a series of encrypted messages — from a documentary in the 1990s. His interest marginally ...

Oranchak, a 46-year-old software developer in Virginia, said the 340 is what’s known as a transposition cipher. Most ciphers used today by computers rely on mathematics to scramble messages.

An international team of code-breakers figured out the 51-year-old Zodiac Killer cipher and revealed its chilling message.

The FBI San Francisco Division on Friday announced it is aware and investigating after the cipher attributed to the Zodiac Killer was recently solved by private citizens.

Previously only one Zodiac cipher had been solved, also by citizens, namely a California couple, back when the killings had just started. This one, however, was considered even more complex.

The Zodiac’s first cipher, included in the July 31 letter, had been solved within a week by an amateur husband-and-wife team—but it had only revealed more of the killer’s raving.

After Golden State Killer case, could DNA be used to find the Zodiac Killer? Amateur codebreakers have solved a decades long mystery. The FBI confirmed Friday that a group of private citizens ...

An international team of code-breakers figured out the 51-year-old Zodiac Killer cipher and revealed its chilling message.

An international team of code-breakers figured out the 51-year-old Zodiac Killer cipher and revealed its chilling message.

An international team of code-breakers figured out the 51-year-old Zodiac Killer cipher and revealed its chilling message.