FERGUSON, Mo. - Tensions reached a boiling point Sunday night following an officer involved shooting that left a teenager dead. The violence began after a planned rally and vigil in the wake of the death of 18-year-old Michael Brown.

Brown was the unarmed teenager shot to death by an Ferguson police officer on Saturday afternoon.

Police officers from every jurisdiction in the St. Louis area were called into Ferguson Sunday evening. The strong police presence became necessary after violence and looting were reported in the area. Witnesses say tensions began rising at the intersection of West Florissant and Ferguson around 8:30 p.m. In response Ferguson police called in an extra 60 officers as well as officers from all surrounding jurisdictions.

Officer Brian Schellman with the St. Louis County Police Department says 200 officers were called to the area from at least two dozen departments, but approximately 300 total officers were in the area. Many officers who were not called in responded anyway.

Two police officers were injured Sunday night during the unrest. One of those officers was hit by a brick, the other suffered a knee injury. They are both expected to be okay. One St. Louis County police officer was shot at, but was not injured.

Police say 32 arrests were made during the chaos. At least 12 businesses were looted. At least one shot was fired at a police helicopter. Rocks, bricks, and bottles were thrown at police officers throughout the night. There's no word on how many patrol cars were damaged.

A focal point of the violent actions by some was the Quiktrip store in the 9400 block of West Florissant. Video obtained by NewsChannel 5 showed the store being actively looted and later, someone set the store on fire.

Additional looting was also reported at a liquor store near the Ferguson Quiktrip, as well as fire reported behind the building where the liquor store is located.

Zisser Tire & Auto in Dellwood was vandalized during the unrest. Windows were smashed in, tires and rims were stolen, tires were thrown through windows, and glass is lining the streets.

Police are staging across the street from the store and watching the area.

A NewsChannel 5 crew reported that tear gas has been dispensed as rioting and looting continued into the early Monday morning hours. Reporter Elizabeth Matthews was preparing for a report from the corner of West Florissant and Highmont Drive, when she began feeling the affects of the tear gas in the area.

"My nose is burning, my eyes are burning, my throat is burning and officers near by are dealing with this too," said Matthews in a live report.

All of this is unfolding along Florissant Avenue, where NewsChannel 5 reporter Elizabeth Matthews and photojournalist Don Galloway were working. Matthews reports seeing more then half a dozen individuals breaking into the store, followed by dozens of others as the looting began.

The day began with Chief Jon Belmar with the St. Louis County Police Department holding a news conference Sunday morning and releasing new information about the shooting death of 18-year-old Michael Brown.

Belmar said the incident started when Brown physically assaulted the police officer, pushing him into the officer's vehicle. He said there was a struggle inside the car, and at some point Brown reached for the officer's weapon. One shot was fired inside the vehicle.

Brown suffered fatal gunshot wounds outside of the vehicle, approximately 35 feet from the car. Belmar said multiple shell casings were found at the scene, and that Brown was shot more than once, but an exact number of shots fired has not yet been determined. All the shell casings came from the officer's weapon.

Belmar confirmed Brown was unarmed at the time of the shooting. He did not say what led to the struggle inside the officer's car.

The medical examiner is conducting an investigation to determine how many times Brown was shot. It will take several weeks before toxicology results are available.

After the shooting, Belmar said Ferguson Chief Tom Jackson called him and asked the county to take over the investigation.

Belmar said when the investigation is complete the findings will be turned over to the St. Louis County Prosecuting Attorney's Office. They will determine if charges should be filed.

On Saturday afternoon the St. Louis County NAACP called for the FBI to investigate the shooting. Belmar said the FBI could become involved later, and that it's not unusual for the FBI to become involved in cases like this.

"My son just turned 18 and graduated from high school, and he don't bother nobody," Brown's mother, Lesley McSpadden, told NewsChannel 5 Saturday night. She said he was looking forward to starting school at Vatterott College next week.

"They told me how many times my son was shot. Eight," said McSpadden. She said he was visiting his grandmother, who lives in the complex, and was returning from the store.

Sen. Claire McCaskill has released this statement in response to Michael Brown's death:

"As a mother, I grieve for this child and his family. I pray that the wonderful, hardworking, and God-loving people of Ferguson will find peace and patience as we wait for the results of what will be numerous and thorough investigations of what happened. I, like so many other Missourians, will not be satisfied until we have a complete and transparent understanding of all the facts and circumstances that led to this young man's death."

Cornell Williams Brooks, president and CEO of NAACP, released this statement:

"Our prayers go out to the family and friends of 18-year-old Michael Brown of Ferguson, Missouri. The death of yet another African-American at the hands of those sworn to protect and serve the community where he lived is heartbreaking. Michael Brown was preparing to begin college, and now his family is preparing to bury their child – his life cut short in a tragic encounter with the police.

"As the NAACP's Missouri State Conference and St. Louis Branches seek answers about the circumstances surrounding Michael Brown's death, the National office will remain vigilant until accountability and justice are served for the countless individuals who lose their lives to misguided police practices throughout the country. Even as we call for accountability by those charged with protecting the community, we call on the community to act--collectively and calmly until we secure justice for the family of Michael Brown."