Florida detectives were watching Robert Hayes on Friday when he gave them a gift.
The 37-year-old Palm Beach, Florida man was allegedly smoking a cigarette at a bus stop by his home on Sept. 13 when he flicked it away.
Eagle-eyed investigators claim they picked up the drag and performed DNA tests on it.
Findings from those tests link Hayes to the 2016 murder of Rachel Bey, of Riviera Beach, Florida authorities confirmed on Monday.
Bey was 32-years-old when authorities say she was strangled and her naked body discovered by construction crews left on a highway near Jupiter, Florida.
“Had we not done this, we’re pretty certain he would have killed again,” Palm Beach County Sheriff Ric Bradshaw told reporters on Monday following an appearance in court by Hayes to face first-degree murder charges, according to The Palm Beach Post.
Hayes was held in jail on charges related to Bey’s murder.
He is expected to be charged for a pair of other homicide cases involving the deaths of two women in Daytona Beach back in 2005 and early 2006, according to the publication.
With Hayes's arrest, authorities believe culminates a decade’s search for the so-called “Daytona Serial Killer.”
"We've been able to take what we believe is a serial killer off our streets," Bradshaw said, as reported by WPEC, a West Palm Beach station.
Hayes is believed to have lived in Palm Beach County during Bey’s death, and living in Daytona Beach when the two other unidentified women perished back in 2005 and 2006.
Authorities weren't going to stop investigating after catching the man they believe is a serial killer.
"I don't care if it's one year, 10 years, 20 years, 30 years, we will keep working every single day, every single hour until we find these monsters that are out there that do these things," Bradshaw said. "I can guarantee you folks if we hadn't put this individual in jail he would've done this again and we would've had another innocent victim out here."
A Florida Department of Law Enforcement spokesman emphasized the value DNA evidence plays in solving crimes.
"Killers like Robert Tyrone Hayes are the reason genetic genealogy is so important to public safety," a Florida Department of Law Enforcement spokesman said in a statement to WPEC. "Without genetic genealogy, predators like Mr. Hayes will continue to live in our neighborhoods, visit our parks, our libraries, restaurants, and go to our nightlife and entertainment districts to continue to hunt for victims."
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