(CNN) -- Police in North Carolina shot and killed a man running toward them Saturday morning -- but he may have just been looking for help after a car wreck.
Officers responded to a "breaking and entering" 911 call at a home in Charlotte.
The homeowner told dispatchers that a man had been knocking on her door repeatedly.
Police say that when they got to the scene, a man matching the caller's description ran toward them.
One of the officers fired his stun gun, but it was "unsuccessful." Another officer then opened fire, police said.
Jonathan Ferrell died at the scene. He was shot several times.
He was unarmed.
Police now believe Ferrell was seeking assistance after crashing his car.
Ferrell was 24 and a former football player at Florida A&M University.
Police found a wrecked car nearby, indicating that he may have been trying to get help.
"It was a pretty serious accident," Charlotte-Mecklenburg Police Chief Rodney Monroe told CNN affiliate WSOC.
The crash was so severe that authorities now believe Ferrell had to climb out of the back window, affiliate WBTV reported.
He ran to the closest house for help.
The woman inside thought it was her husband.
"To her surprise, it was an individual that she did not know or recognize," Monroe told WBTV. "She immediately closed the door, hit her panic alarm, called 911."
The man stood outside and "continued to attempt to gain the attention of the homeowner," a police statement said.
Police have charged Officer Randall Kerrick with voluntary manslaughter -- a felony. He turned himself in Saturday afternoon and was released Sunday on $50,000 bond.
Police used "charged" and "ran" and "advanced" in their description of what Ferrell did.
There were three officers at the scene, but Kerrick was the only one to use a gun.
He fired several times, police said.
"The evidence revealed that Mr. Ferrell did advance on Officer Kerrick and the investigation showed that the subsequent shooting of Mr. Ferrell was excessive," police said in another statement issued late Saturday night. "Our investigation has shown that Officer Kerrick did not have a lawful right to discharge his weapon during this encounter. "
All three officers have been placed on paid leave.
A charge of voluntary manslaughter means the person used excessive force in self-defense, or carried out the act without intent to kill.
Police called the incident "unfortunate."
"It has devastated a family as well as caused a great deal of sadness and anxiety in our organization," a statement said.
Kerrick's first court appearance is scheduled for Monday at 1:30 p.m., the Mecklenburg County District Attorney's Office said.
"In every case, the District Attorney's Office evaluates the evidence available and works to achieve a fair and just outcome," the office said in a statement.
Friends expressed grief on social media, calling Ferrell a "brother" and demanding "justice."
He had at least one brother, Willie, who played with him at Florida A&M.
The university said it was "deeply saddened" at the loss. In a statement, Michael Smith, interim athletic director, said Ferrell played safety and was part of the 2010 championship team. "Our hearts and prayers go out to his family during their time of bereavement," Smith said.
Ferrell was engaged.
"We loved him. Our family loved him," his fiancee's mother told WSOC.
He would have turned 25 next month.
CNN's Rich Phillips, Janet DiGiacomo, John Branch and Emma Lacey-Bordeaux contributed to this report.