Beginning on Sept. 29, 1982, and over the next week, seven people were murdered in the Chicago area after unknowingly taking Tylenol pills that were spiked by a killer. Now, investigators are turning once again to DNA evidence to try to identify the person or people who did it, report CBS Chicago’s Dave Savini, Samah Assad and Rebecca McCann. …

Now, with the case still unsolved, new documents obtained by CBS Chicago reveal an intense effort to use advanced DNA technology to identify the killer. And 40 years later, the Morgan family still finds itself a piece of that puzzle.

The Arlington Heights (Illinois) Police Department (AHPD) is initiating much of the DNA testing and collection as it continues to investigate the deaths of three members of the same family – Adam Janus, Teresa Janus, and Stanley Janus. They all were killed in Arlington Heights after taking poisoned Tylenol.

[Readers may recall that an arrest was made in the Tylenol poisoning cases, but that was for an extortion attempt by prime suspect James Lewis. No one has ever been charged for the murders. Fourteen years ago, Time Magazine wrote a timeline of the case and noted then that police still had the original capsules. At that time, Time noted that police “are hopeful some DNA can be recovered from the pills for testing.” Maybe technology has finally caught up with the killer. — Ed]