A string of murders in Paris has both French police and the public fearing that a serial killer is on the loose in the City of Light after the same semi-automatic weapon was used to gun down four victims over the past five months.

The motorbike-riding gunman shot his latest victim, Nadjia Boudjemia-Lahcenea, 47, of Algerian descent, in the entrance hall of her apartment building in the Grande-Borne district of Grigny on Thursday, before fleeing the scene, reported the Telegraph.co.uk.

Serial killer John Wayne Gacy murdered 33 victims and despite his execution in 1994 by lethal injection, police have reopened the investigation in an attempt to identify all of his victims, RadarOnline.com has learned.

Dozens of families of young men who went missing in Chicago during the 1970s have come forward in the hope of having the fate of their loved ones confirmed once and for all, reported the Chicago Tribune.

The relatives are taking part in DNA testing after the Cook County sheriff's office announced last week that they had exhumed eight skeletal remains of victims of Gacy in order to finally give the John Does names.

His golden movie star looks make him the most unlikely of mass murder suspects but that's exactly what Anders Behring Brevik is, according to Norway authorities.

Now RadarOnline.com has uncovered that Brevik's Facebook page listed Dexter as his favorite TV show.

PHOTOS: Celebs Who Have Done Jail Time

Dexter is the cult hit Showtime series starring Michael C. Hall as a serial killer!

Breivik, a 32-year-old Norwegian native, is alleged to have gone on a killing rampage Friday. He has now been charged with brutally slaying at least 85 people, most of them children, on the island of Utoeya, plus another seven in a bomb blast in Oslo.

PHOTOS: Celebs Involved In Murder

Another five five people are still missing, thought to have fled into the water in an attempt to swim away from the island where hundreds of children were enjoying a summer camp.

Brevik also described himself as a conservative Christian on his Facebook page. He said he's a member of Nordisk, a group with over 20,000 members that focuses on political terrorism.

PHOTOS: Stars Who Died In Bizarre Ways

Described by local media as a 'loner' he had never married and lived with his mother in a wealthy area of Oslo.

Well-educated and handsome, Brevik had started his own organic farm and listed his other interests as body-building and freemasonry on the social networking site.

Just days before the attacks he set up a Twitter account and posted the message: "One person with a belief is equal to 100,000 who have only interests."

PHOTOS: Stars Who Have Been Stalked

It's not yet known why he is believed to have targeted the children at camp.

Facebook has now taken down Brevik's page, but dozens of fake ones have since materialized.

RELATED STORIES:

Mother Tries To Sell Baby At Taco Bell

Casey Anthony Hiding Out On Geraldo Rivera's Yacht? 'Untrue!' Says His Brother

Drugs Boss Releases Statement About Dead Son Following Bizarre Death

Hollywood legend John Wayne must be turning in his grave!

Presidential hopeful Michele Bachmann, who is becoming as famous for her on-air gaffes as she is her Christian right-wing views, made another major faux pas Monday.

The Minnesotan made a triumphant return to her hometown of Waterloo, Iowa to officially announce her run for presidency, but when a microphone was placed in front of her things all went a little awry.

Serial killer and cult leader Charles Manson recently spoke out for the first time in 20 years, referring to himself as God and calling President Barack Obama "an idiot."

"I don't play. I shoot people," Manson told Vanity Fair Spain magazine in a rambling phone interview from his California prison cell. The interview marked the 40th anniversary of his conviction. "I'm too bad. I'm a mean guy. I'm an outlaw. I'm a criminal. I'm everything bad."