JACKSONVILLE, Fla. -

The Jacksonville Sheriff's Office Internal Affairs unit is investigating an assistant police chief after a local couple filed a formal complaint saying they were assaulted by the officer at an Eagles concert in February.

Channel 4 learned Assistant Chief Leonard Propper is the officer under investigation after the incident and spoke to the couple about what happened to them during the concert last month.

The couple asked Channel 4 to disclose their identities, saying they're afraid of the Sheriff's Office after what happened at the concert on Feb. 26.

The wife said she tried to take pictures at the concert and that many other fans were doing the same, despite police and security telling them to stop. The couple said as they were approached by officers, they didn't realize they had also been sitting behind an off-duty police officer.

"An off-duty officer, off-duty. Concert goer, drinking beer, the whole thing," said the couple.

The couple said the situation quickly got out of hand, and Propper turned around and got involved.

"He had no uniform, showed no identification, nothing. He turned around and said, 'Let's get this (explicit) out of here,' grabbed him, pulled him over the seats -- he hit his head on the third row in front of us," said the wife. "His glasses were found 4 rows in front of us."

The couple told Channel 4 that Propper then dragged the husband from the arena with working uniformed officers following behind.

"We are aware that he had that other assault of a citizen off duty prior to this because we searched for his name," said the couple.

Channel 4 found Propper received a complaint last year that claimed the assistant chief threatened a driver with a ticket while he was off-duty. After that incident, Propper was instructed by the Jacksonville Sheriff's Office to get counseling after the incident.

The entire incident was caught on video and posted on YouTube by Jax Dash Cams.

When asked about the incident during the concert, Propper told Channel 4 that the couple's claims are "just an allegation."

"Anybody can make allegations but I can't comment until the process is over," said Propper. "(The) second it's over, I'll provide you with the full report."

The couple said they just hope justice is served.

"I think that says a lot of bad stuff about our police," said the couple. "They take a vow to serve and protect, not assault and injure."

Channel 4 heard from a woman who is friends with Propper Tuesday night. She claimed the couple that was thrown out of the Eagles concert deserved to be.

In an email to Channel 4, Kristy Dutton said she was sitting in front of the couple and next to Propper during the concert.

Dutton said the man was “drunk and disorderly.” She also wrote, “By the 4th or 5th song, security had been up there twice and then finally JSO came up to speak with him. He was freaking out, yelling at the female officer so Officer Proper stood up to try and calm the man down...He was escorted out of the arena because of his behavior and complaints from other concert goers.”

The Jacksonville Sheriff's Office sent Channel 4 this statement about the situation and the investigation into Assistant Chief Proper:

"We can confirm that the Internal Affairs Unit of the JSO is investigating a citizen complaint involving Assistant Chief Leonard Propper. The complaint stems from a possible incident during a citizen ejection from a concert at the Arena."