(CNN) -- The FBI in Seattle, Washington, is looking into allegations of civil rights violations in the case of a police officer caught on video kicking a Latino detainee, an agent said Wednesday.

The preliminary inquiry comes a day after the NAACP sent a letter to the King County prosecuting attorney's office requesting Seattle police Detective Shandy Cobane be charged with malicious harassment, a hate crime.

Video captured by a freelance video photographer April 17 shows Cobane using racial slurs against the detainee and kicking him in the head, and another officer stomping on his leg while he is lying face down on the ground without handcuffs. The second officer was identified this week as Mary Lynne Woollum, Seattle police said.

The detainee was released after officers determined he was a not a suspect in an armed robbery, according to CNN affiliate KOMO.

"We give officers guns, batons and badges with the hope that they will not violate our public trust, with the hope that they will enforce the law, provide public safety and honor the Constitution," James Bible, president of the Seattle chapter of the NAACP, said Tuesday in denouncing the police officers' actions. "In this specific case ... the Constitution was violated in a most egregious way. ... We have no choice but to request that charges be filed."

FBI Special Agent Fred Gutt told CNN Wednesday that investigators will gather information on the incident and send it to the Civil Rights Section of the U.S. Department of Justice.

"They will then decide if a formal investigation is warranted," he said.

Cobane issued a tearful apology Friday after the video was shown on local news stations.

In the statement, Cobane called his comments "offensive and unprofessional" and said they "do not reflect who I am or what I am as a person nor as a member of the Seattle Police Department."

Cobane, a 15-year veteran, and Woollum, a veteran of more than 10 years, have been placed on administrative reassignment while investigations are under way, according to Seattle police.

CNN's Melanie Whitley contributed to this report.