MIAMI BEACH (CBS4) – A Miami Beach Police Lieutenant has been demoted following the ATV accident that left two people injured over the Fourth of July weekend. The lieutenant had just been promoted to the position.

CBS4 News has also learned the Department is also investigating other supervisors in connection with the accident, but police have not released any more details on the lieutenant or other supervisors.

Two Miami Beach police officers, Derick Kulian and Rolando Gutierrez, had already been fired.

Kulian, a five-year veteran of the force, was “present at the Clevelander Hotel and that Officer Kulian took a civilian on his ATV in violation of departmental policies,” according to a Miami Beach Police statement released Tuesday.

The department said that the termination process is “separate and apart from the ongoing criminal investigation underway.”

Miami Beach Police Chief Carlos Noriega gave a strict message at a news conference after the arrests of the officers.

“This is conduct that we have never tolerated and will not tolerate,” said Noriega. “There is no room for this sort of mistake. This was a huge mistake. It will not be tolerated. This is a message to the public and our citizens and to the department that we expect the best type of professional behavior. It is important for our 10 million visitors every year and 90,000 residents. We work too hard for something that leaves everyone with a bad taste. To say that I am upset is an understatement.

He defended the decision not to charge Officer Kuilan, saying that “contrary to some reports,” he did not leave the scene of the accident and he said his blood alcohol test results were not available. “If we find that he is DUI, he will be prosecuted,” said Noriega.

Even if he was not DUI, Kuilan could still be prosecuted for reckless driving or culpable negligence, authorities say.

Chief Noriega said both officers were “distraught” when he met with them.

The City Manager cited dereliction of duties and conduct unbecoming an officer as reasons to fire the men.

Miami Beach Mayor Mattie Bower said, “I think it was very important to show our visitors and our residents that when action like this needs to be taken, it is taken. It was important that the Chief acted swiftly. I feel deeply concerned about this, for those who have suffered, their families and even the families of the police officers.”

The officers still have their state certificates as officers, but Noriega said he would be notifying the Florida Department of Law Enforcement about the firings.

Officer Gutierrez, a six-year veteran of the force, was fired because he was with Kulian at the bar at1020 Ocean Drive. According to police, the officers were drinking while on duty.

Officer Kulian allegedly hit Luis Almonte, 29, and his friend Kitzie Nicanor, 28, with an ATV just after 5 a.m. Sunday.

The accident sent Luis Almonte, 29, to intensive care at Mt. Sinai Medical Center on Miami Beach. Doctors used a rod to fix Luis’ broken femur.

Nicanor, who is from the state of Washington, had her spleen removed, a broken femur and there is a perforation in her heart.