( CNN ) Mystery surrounds the fiery weekend death of Jessica Chambers , but the Mississippi teen may have given firefighters a clue in her killing , a prosecutor said Wednesday . The volunteer fire department that responded to her car blaze Saturday night got there quickly because it was at another call a couple of miles away , said John Champion , district attorney for Mississippi 's 17th Circuit . When firefighters arrived at the scene near Courtland , Mississippi , Chambers approached one of them and spoke . She was not on fire , as has been widely reported , the prosecutor said . Champion did n't divulge what she said but told CNN , `` It has certainly given us a lead we 're following up on . '' Chambers , 19 , was loved by everyone who knew her , older sister Amanda Prince told CNN 's Don Lemon . `` She was crazy . Very athletic . Outgoing . She was just ... Jessica , '' Prince said . `` She was happy all the time . She made everybody laugh . '' Prince said her sister had talked about becoming a nurse and also wanted to become an author . Investigators looking at cell phone . Though authorities are releasing sparse details of the crime and investigation , they have determined an accelerant was used in the blaze , but it 's not clear whether the accelerant was poured on the car or Chambers herself , Champion said . The state fire marshal is processing the evidence to determine what type of accelerant , and it 's possible the evidence will need to be sent to the Bureau of Alcohol , Tobacco , Firearms and Explosives in Atlanta , he said . Prince said she was told the attacker had gotten into the car and set Chambers on fire inside the vehicle . Peter Odom , an attorney who prosecuted some arson cases , told HLN 's `` Nancy Grace '' that investigators are looking for something in particular when they interview people involved in the case . `` They 're looking for someone with singed eyebrows and maybe burned hands . Because the burner often gets burned , '' he said . Investigators believe her phone will be `` the key to everything , '' the prosecutor said . She received a call before she left her house , he said . An autopsy was performed but results have not been made public . Sister : She was supposed to come home . Despite reports she was going to a party , her appearance -- her hair was in a bun and she was wearing camouflage pajama pants -- suggests that was n't the case , Champion said . Police have also spoken to partygoers , who do n't recall seeing her there , he said . Prince said her sister called their mother from a gas station and said she would be home right after she cleaned her car . The prosecutor also said investigators found no evidence in a store surveillance video that appears to show Chambers prepaying for gas . She walks to the store 's front door when something or someone catches her attention . She waves and walks off camera briefly , comes back into the camera 's view , enters the store where three men chat by the doorway and spends about a minute at the counter before going back outside and pumping gas . The business , which Champion characterized as a rural mom-and-pop store , is about 2 miles from Chambers ' home . She purchased something to drink there , the prosecutor said . The clerk who helped her said nothing seemed out of sorts . `` She seemed normal , '' Ali Alsanai told CNN affiliate WREG . `` She did n't seem like something was going wrong , you know ? She just seemed normal . She just pumped some gas , we had a talk , and she left . '' A Facebook page titled Justice for Jessica has drawn more than 75,000 likes and that number was climbing rapidly Wednesday . The page states it was created `` to keep Jessica 's name alive & out there . '' `` They have ripped everything I have , '' Jessica 's mother , Lisa Chambers , told CNN affiliate WMC . CNN 's Steve Almasy , Dave Alsup and John Murgatroyd contributed to this report .
Jessica Chambers ' words to firefighters have `` certainly given us a lead , '' prosecutor says . DA : Investigators believe she received call , her phone will be `` the key to everything '' Emergency responders found her badly burned on a rural road in Panola County , Mississippi . The fire was reported at about 12:30 a.m. Friday morning and quickly spread across more than 100 acres of land near the town of Pinson.