During a press conference on Friday, December 17, Fairfax County Police Chief Kevin Davis said Robinson, who was taken into custody and charged with killing two people last month, may be involved in the deaths of at least two additional women.

Police claim the 35-year-old met his victims on dating websites and reportedly lured them to motels. They alleged he would then kill them and use shopping carts to transport their bodies to vacant lots in an attempt to cover his tracks.

Allene Elizabeth “Beth” Redmon, 54, and Tonita Lorice “Nita” Smith, 39, were two of the victims who were found last month in Harrisonburg. Authorities now believe Robinson is also responsible for the death of a woman they identified as Cheyenne Brown, 29, as well as another unidentified victim from Fairfax.

“We’re in the process of conducting, along with many other partners, a retrospective investigation to figure out where he’s been,” Davis said. “And we’re going to work with our law enforcement partners, homicide detectives, missing person detectives, to see if we can identify any other victims and families and communities that he has brought harm to.”

While police were initially unable to locate Brown in the area where she was last spotted, a tip led them back to the same location and they eventually noticed a shopping cart in the distance.

Investigators found two bodies in the shopping cart, including one they believe is that of Brown and another unidentified woman.

“We have a tattoo that’s been positively identified by her family as Cheyenne’s tattoo, and the reason why we’re not waiting … until we get positive and 100 percent positive DNA or dental verification that it is Cheyenne, is because we believe that there may be other victims in the area and throughout the Commonwealth of Virginia,” Davis said. “And we need to act now.”

According to PEOPLE, Robinson was originally charged with two counts of first-degree murder in addition to two felony counts of concealing, transporting or altering a dead body. He has not been formally charged in relation to the newly discovered women, but police say they are forthcoming.

According to The Associated Press, Robinson is scheduled to appear at a hearing on December 27.