The mother of a Brooklyn teenager shot and killed by police demanded an investigation Thursday, saying he was "slaughtered" and that she wants to know why.

Kimani Gray, 16, died over the weekend. His death triggered protests in Flatbush, a community in Brooklyn where distrust of the police runs deep.

"I'm still waiting for Kimani to come home," Carol Gray told reporters during an emotional news conference. She wore dark sunglasses and struggled to speak as she recalled picking the color of her son's casket.

"He has a curfew," she said. "Sometimes he's late. Sometimes he's early depending on the night. But whatever time he gets there, I'll be real happy to see him as soon as the bell rings. And for the past couple of days, the bell hasn't rung."

According to police, plainclothes officers were on patrol in their car in Flatbush when they saw a group of men gathered on the street at about 11:30 p.m. Saturday.

As the officers got closer, Kimani Gray broke from the group and adjusted his waistband. The teen "continued to act in a suspicious manner," so the officers got out of their unmarked car and tried to get his attention, said a NYPD statement.

Kimani Gray then "turned on them," it said, and pointed a .38-caliber revolver at the officers. They fired at the teenager, striking him.

The teen died at a hospital, and a loaded .38 was recovered from the scene, the statement said.

One officer fired four rounds; another fired seven, according to NYPD Deputy Commissioner Paul Browne. Both are now on administrative duty.

The officers were taken to a hospital and treated for what the department described as trauma and tinnitus, a ringing in the ears.

Gray said that her son was killed in front of his best friend's house. She described him as a typical teenager, into girls and hanging out with friends.

Most people in the city likely don't believe what police say happened Saturday, said Councilman Charles Barron, who appeared with the teen's mother at the news conference.

For her part, Carol Gray said she did not think her son had a gun, but added, "I wasn't there."

"He is not the public's angel, but he's my angel, and he's my baby, and he was slaughtered and I want to know why," she said.

By Monday, anger at the shooting boiled over, with a mob of young people interrupting a vigil by running wildly into local businesses, according to an eyewitness. Police said they arrested two people that day.

On Tuesday, another protest brought out a mostly calm crowd that returned Wednesday, anticipating that Gray's mother would speak, said iReporter and professional photographer Joel Graham.

But the hope for a peaceful crowd faded when about 30 young men showed up across the street from the vigil, he said.

"They were not coming out of the shadow. They were staying in the dark area of the street. You just knew it was going to turn into the cops trying to contain those kids who were obviously gonna go for it," Graham said. "That just stopped the original intention of the night."

Graham began to take photos, watching as kids crossed the street toward the protesters. Community leaders started shouting for everyone to calm down and asked anyone taking pictures to stop so they could talk to the young men and calm things down, the photographer told CNN.

"These kids broke loose and took off. The police were caught off-guard," Graham said. "Those kids really know the streets, and they're spreading out and going down side streets away from the main street."

Next came the sound of breaking glass and rolling trash cans, Graham said, and business owners quickly pulled down their metal store-front security coverings.

One officer received a gash to his face while another was pushed off his scooter, police said.

Forty-six arrests were made, including two juveniles, with the majority charged with disorderly conduct.

On Thursday, Mayor Michael Bloomberg offered condolences to Gray's family and said that more must be done to stop gun violence.

"I can promise you that we will conduct a full and fair investigation," he said. "I understand there's anger in the community, but the ways to get answers is not through violence or law breaking. We cannot tolerate that and we will not tolerate that."