Authorities are investigating the death of a reportedly suicidal 18-year-old they say shot himself in the face after exchanging gunfire with responding police -- an account his father called "a total lie."

Amonderez Green of Florissant died about 4:30 a.m. Thursday at a hospital, more than 14 hours after the shooting Wednesday in Normandy, adjacent to the St. Louis suburb of Ferguson where the August 2014 police shooting death of 18-year-old Michael Brown stoked distrust of police among minorities.

Normandy police said the confrontation happened about 2 p.m. Wednesday, when Green was being followed by relatives who were "seeking police and medical intervention." When confronted by officers, Normandy police Cpl. Tameika Sanders said, an uncooperative Green pulled out a gun and opened fire on them. Sanders said one of the officers shot at Green but missed, and Green ran off. Officers later heard a gunshot and found Green wounded, a gun nearby, Sanders said.

At some point during the confrontation, police said, an officer tried to subdue Green with a stun gun, but that didn't work.

Green's father, Jermell Simpson, told the St. Louis Post-Dispatch he doesn't believe the police account that his son shot himself, calling that "a total lie." Simpson added that although his son had been upset before the shooting, Simpson and other relatives told a responding officer they "had it covered."

Deron Smith, a resident of the neighborhood, said he heard six to eight gunshots behind his home, went outside to investigate and saw a man running from police as several people behind the officers implored him to stop fleeing. The man did not appear to be holding a gun at that time because he used both hands to scale fences, Smith said.

Smith said he lost sight of the man between two houses, then heard several more gunshots and saw the injured man facedown near a tree.

The officer who fired at Green is a 12-year veteran of the Normandy force, police said. The other officer is a 19-year veteran of the department.

Normandy officers do not have body cameras, which activists increasingly have demanded to be used by police after Brown's death last year in Ferguson.

Brown, who was black, was 18 and unarmed when he was killed by white Ferguson police officer Darren Wilson during a confrontation in a street. The Justice Department later cleared Wilson, concluding evidence backed his claim that he shot Brown in self-defense.

Brown's death helped fuel the national "Black Lives Matter" movement rebuking police treatment of minorities.