On Monday, police said they had two men "of interest" in custody in connection with the shooting. By Tuesday, the case against the men had fallen apart as detectives determined that the tipster who accused them was lying to get out of a drug debt.
Now, police must rely on the surveillance video and additional tips that investigators are "putting on the forefront," Homicide Capt. James Clark said Tuesday.
In the video, the source said, two men with their heads down and hoodies pulled up walk toward Long and her mother.
The men flank the women. One snatches Stephanie Long's purse, while the other grabs Amber Long's bag.
For an instant, she pulls back, the source said, and the gunman fires a shot into her chest.
The men run north on Front Street, Stephanie Long's purse in hand.
Amber Long staggers toward her mother, the source said, then falls and curls up in the fetal position at her feet.
Clark on Tuesday called the crime "vicious" and vowed to find the men responsible, with help from video footage and new tips.
He also expressed frustration over Monday's false lead.
Early Monday, police received information that two men in a house on North Camac Street in Fern Rock had Long's mother's purse, credit cards, and a gun. Police obtained a search warrant and brought six people to headquarters for questioning.
At a news conference Monday, Clark said the two men accused by the tipster matched the description of the killers and added that police hoped to make an arrest soon.
But when police searched the dilapidated home, Clark said, they found nothing, and the men "of interest" had alibis that checked out.
They were released Tuesday morning - and the tipster who allegedly lied to police, Lamar Beatty, was charged with providing false information.
Clark said Beatty, 44, of East Germantown, owed the men a drug debt and tried to get out of it by implicating them in a murder. Clark said Beatty got the idea after seeing news coverage of the killing.
Pressed by investigators, he said, Beatty admitted that he had made up the story.
Clark said investigators were "not starting at zero."
Still, "it's very frustrating to us," he said. "We thought we were very close in locking up the individuals responsible for this really vicious murder. Now we find out that we're not as close as we thought we were."