(ALEXANDRIA, Virginia) -- Virginia police believe they have found a fifth victim linked to an alleged serial killer dubbed the "shopping cart killer," as authorities identified two others and continue to search for more.
The update comes nearly a month after authorities announced that a suspect who was previously charged with the murders of two women whose bodies were found in a lot in Harrisonburg is also believed to be connected to the deaths of two more women whose remains were found in a wooded area of Alexandria in Fairfax County.
The possible fifth victim, also a woman, was found covered by a blanket in a shopping cart on Sept. 7 in Washington, D.C., by a passerby, who reported the discovery to police, authorities said.
The Fairfax County Police Department said it received a tip this week that their suspect in the Alexandria murders, 35-year-old Anthony Eugene Robinson, of Washington, D.C., may be linked to the D.C. case.
"We believe this may be Anthony Eugene Robinson's fifth victim," Fairfax County Police Major Edward O'Carroll said during a press briefing Friday night. "This is based on digital evidence that puts him in the same vicinity around the time of the victim's disappearance. It's sad and tragic."
The body of Sonya Champ, 40, was found near Union Station in a shopping cart, according to the Metropolitan Police Department. The case is currently under investigation. Fairfax County police said they are sharing information with MPD during the death investigation.
Fairfax County police also said Friday they have positively identified the two victims found in Alexandria as Cheyenne Brown, 29, of Washington, D.C., and Stephanie Harrison, 48, of Redding, California. Police initially had believed Brown to be one of the victims, based on distinctive tattoos identified by her family, but were awaiting DNA confirmation.
The remains of the two women were found on Dec. 15 near the Moon Inn in a container next to a shopping cart, police said. Robinson is the primary and sole suspect in their murders, Fairfax County Police Chief Kevin Davis said.
"Robinson was the last person to be seen alive with Cheyenne," Davis told reporters Friday. "Cheyenne interacted with Robinson on the Plenty of Fish dating app. It is believed that Robinson used this Plenty of Fish dating app to lure his victims. We believe Robinson has also used the Tagged dating app."
Cellular data placed Brown and Robinson at the same location on Sept. 30, the night of her disappearance, police said. Receipt records also showed that they stayed at the Moon Inn on the same day, and that Robinson has stayed at that motel on at least five other occasions, Davis said Friday.
Robinson was also charged in connection to the murders of two Virginia women found dead on Nov. 23 near each other in an open lot in the commercial district of Harrisonburg, police said. Video surveillance and cellphone records connected him to the two victims, according to Harrisonburg police.
Authorities allege that both women -- Allene Elizabeth "Beth" Redmon, 54, of Harrisonburg, and Tonita Lorice Smith, 39, of Charlottesville -- connected with Robinson through dating sites and met him on separate occasions at a hotel.
Their bodies were found with blunt force trauma, and investigators said they believe the women were transported to the scene in a shopping cart.
Robinson has been charged with two counts of first-degree murder and two felony counts of concealing, transporting or altering a dead body. His attorney, Louis Nagy, said he is not commenting on the charges or allegations when previously connected by ABC News.
Fairfax County police said Robinson, who is currently incarcerated in the Rockingham County Adult Detention Center while awaiting trial on the Harrisonburg homicides, will face additional charges in their cases.
"Thankfully, he's incarcerated and it gives us the ability to work backwards while he's still not out there killing," Davis said. "The fact that he is awaiting trial in Harrisonburg, Virginia, allows us to continue to build our probable cause to charge him eventually here in Fairfax County."
Detectives are looking for anyone who may have connected with Robinson on dating apps as part of their investigation.
"We believe there are survivors out there," Davis said. "We remain very determined to continue to dig deep and get to the bottom of this."
ABC News' Benjamin Siu contributed to this report.