Authorities identify suspect wanted in fatal shooting of Memphis police officer during traffic stop

A suspect has been identified in the search for a gunman who shot and killed a Memphis police officer during a traffic stop, the city's police director said Sunday night.
A warrant for first-degree murder has been issued for 29-year-old Tremaine Wilbourn, who is believed to be the shooter, Police Director Toney Armstrong said at a Sunday evening press conference.
Wilbourn is currently on supervised release for a 121 month sentence for robbery of a banking institution, Armstrong said.
Officer Sean Bolton, 33, may have interrupted an illicit drug transaction when he encountered a Mercedes-Benz illegally parked on a Memphis street Saturday night, according to Armstrong.
After Bolton illuminated the Mercedes with his spotlight, he approached the vehicle and was confronted by its passenger, who allegedly shot Bolton multiple times after a struggle, the director said.
Armstrong told reporters that 1.7 grams of marijuana was found inside the vehicle.
 "He's a coward," Armstrong said of the suspect, Wilbourn, "you gunned down, you murdered a police officer, for less than 2 grams of marijuana. You literally destroyed a family."
“Last night we lost an officer and a great man, a dedicated servant and family member,” Armstrong said.
The police director said that the White House has contacted the department and is aware of the incident.
The United States Marshals Service has offered a $10,000 reward for Wilbourn’s capture.
The driver of the vehicle turned himself in to authorities Sunday morning, and has since been released without charge, Armstrong said at the press conference.
Police were initially alerted about 9:18 p.m. Saturday that an officer had been shot multiple times. Armstrong said the officer was transported in critical condition to a hospital, where he died.
In a statement Sunday morning, Memphis Police said that a civilian had used Bolton's radio to notify police about the shooting.
Armstrong said police are using all available resources to find the shooter and that officers are grieving, adding that "this is just a reminder of how dangerous" the job is.
"Sadly to say, we've been here before," he said.
Bolton is the third Memphis officer to be fatally shot in slightly more than four years. Officer Tim Warren was killed while responding to a shooting at a downtown Memphis hotel in July 2011. In December 2012, Officer Martoiya Lang was killed while serving a warrant.
Memphis Mayor A.C. Wharton Jr. said Bolton's death "speaks volumes about the inherent danger of police work" and asked others to "pray for the family and pray for our city."
"The men and women in blue have certain rules of engagement that they have to follow, but at any given minute in a 24-hour day they're dealing with folks who have no rules of engagement