FORT LAUDERDALE, Fla. (Reuters) - Prosecutors charged a Florida police officer on Wednesday in the shooting last July of an unarmed black man who was seen on cellphone video lying in a street with his hands in the air at the time he was shot in the leg.

North Miami Police Department officer Jonathan Aledda was charged with attempted manslaughter, a felony, and culpable negligence, a misdemeanor, according to the Miami-Dade State Attorney's office.

The shooting of behavioral therapist Charles Kinsey, who was with and caring for a severely autistic man when he was shot, was one in a series of police shootings of black men across the United States to raise questions about police use of force and civil rights.

7 PHOTOS Charles Kinsey shooting See Gallery Charles Kinsey shooting Healthcare professional Charles Kinsey, shot by a North Miami police officer on July 18 while trying to protect an autistic patient, made his first public appearance Thursday July 28, 2016 in Aventura, Fla. He met with his patient Arnaldo Rios earlier in the day at Aventura Hospital. Kinsey stands with his attorney, Hilton Napoleon II, right, as he describes his reunion with Arnaldo Rios. (Carl Juste/Miami Herald/TNS via Getty Images) North Miami Police officer now facing charges in shooting of behavioral therapist Charles Kinsey. Latest info: https://t.co/sKJEabhdn8 Mathew Dietz, left, stand with Gladys Soto, the mother of Arnaldo Rios, as she speaks to media about Charles Kinsey and Arnaldo Rios' earlier meeting at Aventura Hospital on July 28, 2016 in Aventura, Fla. (Carl Juste/Miami Herald/TNS via Getty Images) Gladys Soto, the mother of Arnaldo Rios, gestures as she describes the hug between Arnaldo and Charles being reunited on July 28, 2016in Aventura, Fla. Kinsey met with his patient Arnaldo Rios earlier in the day at Aventura Hospital. (Carl Juste/Miami Herald/TNS via Getty Images) Officer who shot behavioral therapist Charles Kinsey charged with attempted manslaughter and culpable negligence.… https://t.co/cw7tM8q9lX North Miami Police Chief Gary Eugene speaks at a press conference regarding Charles Kinsey, an unarmed caretaker shot by police while on the ground with his hands up, Thursday, July 21, 2016 in Miami. (Carl Juste/Miami Herald/TNS via Getty Images) Congresswoman Frederica Wilson speaks at a press conference regarding Charles Kinsey, an unarmed caretaker shot by police while on the ground with his hands up, Thursday, July 21, 2016 in Miami. (Carl Juste/Miami Herald/TNS via Getty Images) Up Next See Gallery Discover More Like This HIDE CAPTION SHOW CAPTION of SEE ALL BACK TO SLIDE

Aledda defended his actions last July, saying "I did what I had to do in a split second." The Miami-Dade Police Benevolent Association, which is representing Aledda, was not immediately available for comment.

The officer was responding to reports of a man with a gun and apparently was aiming at the autistic man when he shot Kinsey, according to an affidavit supporting the arrest warrant filed with the state court for Miami-Dade County.

Kinsey had followed police commands and was lying on the ground at the time he was shot. He had been trying to get the autistic man back to a nearby group home from which he had wandered. Hilton Napoleon, a lawyer for Kinsey, was not immediately available for comment.

#BREAKING: North Miami Police officer faces criminal charges in shooting of unarmed caretaker https://t.co/qakmv0aAJOpic.twitter.com/jnLm1Ku6ez — WSVN 7 News (@wsvn) April 12, 2017

Initial calls to 911 emergency dispatchers reported a man, possibly suicidal, with a gun in his hand, which led to the arrival of 16 police officers, including Aledda. What a caller thought was a gun turned out to be a toy tanker truck held by the autistic man, according to the affidavit.

The affidavit said the autistic man, who is now 27 and has an IQ of 40, needed around-the-clock supervision.

In a video widely shared on social media, Kinsey can be heard yelling, "All he has is a toy truck in his hands."

The affidavit said Aledda fired three shots using his personally owned Colt M4 Carbine rifle from about 150 feet where Kinsey lay.

"No other officer on the scene observed (the autistic man) exhibit any behavior that compelled them to shoot," the affidavit says.

(Reporting by Bernie Woodall; Editing by Daniel Trotta and Andrew Hay)