By Amir Vera, CNN

(CNN) -- Cambridge police have launched an internal investigation after a video showed officers tackling and punching a naked black Harvard student who police said was resisting arrest.

According to a police report on the incident, officers responding to multiple calls about a disturbance at a busy intersection late Friday found Selorm Ohene, 21, naked and acting in an "aggressive, unreceptive, and intimidating" manner. They were also told by Ohene's friends that he had possibly taken LSD or another hallucinogenic drug, the report said.

Police said they tried to reason with Ohene but he became more hostile and would not comply with their demands, so they took him down, according to the report. He still would not allow the officers to handcuff him, so one officer "delivered approximately 5 strikes with a closed fists to the area of his stomach. These seemed ineffective," the police report said.

Ohene was eventually handcuffed, shackled and placed in an ambulance, where he spat blood and saliva at the emergency medical technicians, the report said. He has been charged with indecent exposure, disorderly conduct, resisting arrest, assault, and assault and battery on ambulance personnel, the police report said.

'Video speaks for itself,' attorneys say

Lawyers for Ohene said in a statement Tuesday their client, who is studying mathematics at Harvard, is recovering from injuries "sustained during his encounter with the Cambridge Police Department."

CNN affiliate WCVB reported the student was in police custody as of Monday evening, but was in a hospital undergoing a mental evaluation. It's unclear from the police report what his injuries are, or the severity of them.

"This has been and continues to be a trying ordeal for Selorm and for his family," said his attorneys, Prof. Ronald S. Sullivan Jr., who is the director of Harvard Law School's Criminal Justice Institute, and Prof. Dehlia Umunna, the deputy director of the institute.

"Although there has been significant extrajudicial commentary on Selorm's case, we do not intend to litigate these matters in the media. As the public is aware, several students captured the incident on their cell phones. The video speaks for itself. At this time, our focus is on Selorm's health and well-being," the attorneys' statement added.

Harvard University President Drew Faust called the incident "profoundly disturbing."

"A Harvard student was in obvious distress, and we need to understand how that came to be and whether we could have interceded earlier and more effectively," she said in a statement Monday.

"We do not yet know all the facts, and it will take time before the necessary reviews have been completed and we have a fuller understanding of events leading up to the incident and the incident itself. But what we do know raises important issues about the relationship between police and the communities they serve, student health resources, and the manner in which University units operate with each other and with our partners in the community," Faust said in the statement.

What happened

Officer Steven Burke said in the incident report that after officers' efforts to calm down and reason with Ohene failed, he saw the man clench both of his fists and take steps toward another officer. He described Ohene's behavior as "chaotic and tumultuous."

"I perceived this as a threat and thought an attack was imminent," Burke said in the report. "It should be noted that Ohene is approximately 6 feet tall with a muscular build."

A video of the incident shows one officer tackling Ohene from behind as he walked toward another officer. Ohene then yells as three other officers jump on him.

Two officers were treated at a hospital for minor injuries and unprotected exposure to body fluids, police said.

The Cambridge Police Department's leadership and Professional Standards Unit will conduct an internal review of the incident, per department policy.

"Use of force was required in order to effectuate the male's arrest," Cambridge Police Commissioner Branville G. Bard Jr. said in a statement. "In a rapidly-evolving situation, as this was, the officers' primary objective is to neutralize an incident to ensure the safety of the involved party(ies), officers and members of the public."

Outrage grows

The Harvard Black Law Students Association said in a statement Saturday that Harvard has "ample resources that could have, and should have, been mobilized to come to the student's aid" before police were called.

"The conduct of the CPD on the evening of April 13, 2018 was unacceptable," the statement read. "We are reminded, as soon-to-be-graduates of an elite law school that we cannot protect our bodies with our degrees -- and that is why we also call our current students and alumni to embrace these demands as inclusive to all Black people, not just Harvardians."

The organization is demanding that Harvard University and the university's health services and police department create an internal crisis response team to support students, faculty, and staff that does not involve Cambridge police. They're also calling for the school, students and instructors to put pressure on the Cambridge Police Department.

The association wants the officers involved in the altercation be held accountable and investigated. They also called for police to respect people's First Amendment right to record video of police activity. There were about 30 onlookers during the incident, police said.

Bard said Monday authorities have no evidence that police asked people to stop filming the incident, but if there is such evidence, the department wants to know.

"We would want to be aware of that because that would be in violation of our policies," Jeremy Warnick, the communications director for the Cambridge Police Department, told CNN Tuesday.

Cambridge Mayor Marc C. McGovern said "what is shown on the video is disturbing."

"We have high standards for our police officers in Cambridge. In most cases, the extensive training our officers go through results in the de-escalation of dangerous situations. When confrontations cannot be averted and include the use of physical force, we must be willing to review our actions to ensure that our police officers are providing the highest level of safety for all," he said in a statement Saturday.

Faust, Harvard's president, added that witnessing a use of force incident against a member of the Harvard community was "upsetting and compels the search for a deeper understanding."

"Over the coming days, we will be seeking to determine what Harvard, as an institution, can learn from the incident," she said.