An FBI communications expert testified Wednesday cell tower data placed a phone linked to a suspected killer close to the Canoga Park street where a high school soccer player was murdered in 2012.

Special agent Chad Fitzgerald, who's assigned to a special FBI cellphone analysis team, said a 44 second call made minutes after the murder must have been placed from an area about a mile north of the home where 17-year-old Francisco Rodriguez was shot to death. 

The testimony on the third day of the trial of 24-year-old Jason A. Schumann in Van Nuys was presented to try and prove Schumann and his girlfriend, Elizabeth Ibarra, were close to the crime scene at the time of the murder. 

Fitzgerald said the phone used to place the call was registered to a prepaid Sprint wireless account under the name Wilbert Guardado at Ibarra's parents' address. 

Later, an LAPD detective testified a stolen immigration identification card bearing the same name was discovered during a search of Schumann's Calabasas townhouse. 

Police said Schumann probably killed Rodriguez out of jealousy, after Schumann learned the El Camino High School soccer player had become friends with Ibarra while Schumann was serving time in L.A. County jail in 2011. 

Earlier Wednesday, Ibarra's sister told jurors she overheard Schumann bragging he always carried a handgun, and said she couldn't understand why her sister stayed with him. 

"When I asked her to leave him she said she wasn't going to - she was scared - they had a baby together," the sister said. 

L.A. County Deputy District Attorney Beth Silverman also tried to offer jurors more circumstantial evidence linking Schumann to the shooting. 

LAPD Detective Jeff Briscoe testified he found a single unfired round of 40-caliber ammunition during a search of Schumann's bedroom, and two other baggies of unfired 40-caliber ammunition in Schumann's parents' room. 

On Tuesday an LAPD firearms analyst testified a 40-caliber handgun was used to murder Rodriguez. 

-- Eric Leonard at Van Nuys Court