Investigators said they received a tip that three Florida siblings accused of firing shots at a Florida police car and then robbing a bank in south Georgia may have traveled to Tennessee.
Valdosta Police Commander Brian Childress said he received several leads over the weekend, including separate calls saying the siblings' vehicle was spotted near Forsyth, Ga., and Chattanooga.
Childress said state and federal authorities are checking out the leads. The FBI did not immediately comment.
Meanwhile, the mother of the three fugitives is pleading for them to surrender.
Barbara Bell of Palatka, Fla., mother of Ryan Dougherty, 21; his sister Lee Grace E. Dougherty, 29; and half-brother Dylan Dougherty Stanley, 26, said she fears that hopes are fading for a peaceful ending.
"Only Mom knows what good people you are inside," Bell told Tampa television station WFTS. "Please prove me right and everybody wrong by doing the right thing now and turning yourselves in.
"Your lives are not over. You've made some bad mistakes, but so far no one has been physically harmed," Bell said. "The only safe thing, the only right thing, the only good thing to do is to turn yourselves in."
The three armed suspects, all dressed in black, entered a Valdosta bank last Tuesday, fired shots into the ceiling and demanded money, the FBI said.
At least two of the robbers showed weapons, including one described as being an AK-47 type assault rifle and the other appearing to be an automatic pistol, the FBI said. The other robber grabbed an undisclosed amount of money. The trio left the bank in a white 2006 Subaru Impreza with New York license plate FBE-5900.
Earlier that morning, a police officer in Zephyrhills, Fla., about 200 miles south of Valdosta, tried to pull the group over for speeding, the FBI said.
A patrol officer was chasing the car when one of the suspects began shooting at his police cruiser, disabling it. The officer was not injured and the siblings got away, the FBI said.
The Pasco County Sheriff's Office also is investigating whether the siblings are connected to gun parts found at Tampa International Airport Wednesday morning.
According to TBO.com, the website for the Tampa Tribune, the siblings have lived in Lacoochee in Pasco County for the last three years.
Ryan Dougherty was sentenced Monday to 12 years' probation on charges of lewd and lascivious conduct involving a victim younger than 16 and sending harmful material to a minor.
Bell told The Associated Press her son Ryan was upset over the terms of his probation because he would not be able to see his son who is due to be born within the coming week.
"That could have triggered it," Bell said of the crime spree.
He was wearing an ankle monitor but cut it off before the shooting, TBO.com said. Pasco County sheriff's officials said he has 13 felonies on his record.
Deputies said Dougherty sent his mother a troubling message after the shooting: "At some point we all have to die."
In Florida, more than 100 billboards have gone up statewide with information about the three siblings, according to Channel 2 Action News.
-- The Associated Press contributed to this article.
