Tennessee Police department said officers in Memphis face disciplinary action after the death 29-year-old Black driver following a traffic stop sparked outrage in the community.

Relatives of the victim Tyre D. Nichols have accused police of beating Nichols and causing him to suffer a heart attack.

Authorities have said Nichols experienced a medical emergency after running from officers. Officials said a cause of death has not yet been determined.

Memphis Police Chief CJ Davis said Sunday that the department was serving notice to the officers involved concerning policy violations. Davis said the administrative process was expected to be completed later this week.

"After reviewing various sources of information involving this incident, I have found that it is necessary to take immediate and appropriation action," Davis said in a statement.

The statement did not indicate how many officers were involved.

"Make no doubt, we take departmental violations very seriously and, while we must complete the investigation process, it is our top priority to ensure that swift justice is served," Memphis Mayor Jim Strickland said in the statement.

"We want citizens to know that we are prepared to take immediate and appropriate actions based on what the findings determine."

Police said Nichols, of Memphis, was stopped along a street for reckless driving on Jan. 7. There was a confrontation as officers approached the driver and the suspect ran before officers again confronted and arrested him.

Nichols then complained of shortness of breath and was taken to a hospital by ambulance in critical condition.

The Tennessee Bureau of Investigation said Nichols died on Jan. 10. The bureau is conducting a use-of-force investigation at the request of Shelby County District Attorney General Steve Mulroy.

Relatives told news outlets that the officers who pulled over Nichols were in an unmarked vehicle and that he suffered cardiac arrest and kidney failure because of a beating by officers. Memphis police referred questions to the state bureau, which said it was still investigating.

In a statement Monday on Twitter, civil rights attorney Ben Crump said he is representing Nichols’ family. Crump called for Memphis police to release body camera and surveillance footage from the traffic stop.

"This kind of in-custody death destroys community trust if agencies are not swiftly transparent," Crump said.

An email left with Memphis police asking about the release of the footage wasn't returned.