The family of Tyre Nichols and their attorneys sent a letter to the United Nations urging its human rights division to take action in the “torture and extrajudicial killing” of the unarmed Black man at the hands of Memphis, Tenn., police officers and other similar incidents.

“The United States of America’s failure to appropriately respond to and address police violence and extrajudicial killings of persons of African descent constitutes an abridgement of their human rights,” the letter to the United Nations Office of the High Commission for Human Rights reads, The Independent reports.

Shocking police bodycam video shows several officers pulling Nichols, 29, from his vehicle during a Jan. 7 traffic stop for alleged reckless driving and viciously beating him for no apparent reason. Nichols, father of a 4-year-old son, died three days later in a hospital. According to authorities, the traffic stop led to a “confrontation” and Nichols fled the scene on foot as he was pursued by officers.

According to The Independent, the letter was signed by Nichols’ mother RowVaughn Wells and her attorneys, Benjamin Crump and Antonio Romanucci, and Judge Peter Herbert OBE, Chair of Society of Black Lawyers in the United Kingdom, with support from Jasmine Rand and Yetunde Asika, international legal counsel to the family.

The family is demanding justice and transparency. Authorities charged five former officers, all African Americans, with murder on Jan. 26 for their involvement in Nichols’ death. A sixth officer, Preston Hemphill, who is white, was terminated Feb. 3 but not charged criminally.

According to Memphis station KAIT, an internal police probe found that Hemphill initially lied about seeing Nichols driving recklessly and that Nichols fought officers and tried to grab his partner’s gun, which was not seen on the police video. The footage revealed that Hemphill is heard saying that he used a stun gun against Nichols and declaring, “I hope they stomp his [expletive].”

Crump has suggested that Memphis police officials have “shielded and protected” Hemphill compared to the swift termination and charges against the Black officers. Meanwhile, officials relieved a seventh police officer from duty without naming that person or revealing their role in the brutal beating.

“We demand the immediate arrest of Preston Hemphill, and all of the other officers who took any action that contributed to the death of Tyre Nichols,” Rand told The Independent.

The letter made 11 demands, including mandating all U.S. law enforcement departments use body cams, the immediate release of video and audio recordings after police-involved killings, and the end of qualified immunity that protects police officers from individual liability in many cases.

Meanwhile, independent U.N. human rights experts express serious concerns Feb. 10 about the police-involved killings of Nichols and Keenan Anderson at the hands of Los Angeles officers.

“The brutal deaths of Keenan Anderson and Tyre Nichols are more reminders of the urgency to act,” said Yvonne Mokgoro, chairperson of the UN Human Rights Council-appointed International Independent Expert Mechanism to Advance Racial Justice and Equality in the context of Law Enforcement, U.N. News reported.

Anderson, a 31-year-old father and English teacher, died from cardiac arrest after he was repeatedly tased by police on Jan. 3, marking the third officer-involved death in the city just days into the new year. He’s the cousin of Black Lives Matter co-founder Patrisse Cullors.

The experts asked U.S. officials for details about the death of Anderson and Nichols “on the ongoing investigations and regulations applicable to the use of less-lethal weapons vis-à-vis applicable human rights standards.”

“In both cases, the experts stressed that the force used appears to have violated international norms protecting the right to life and prohibiting torture or other cruel, inhuman or degrading treatment or punishment. It is also not in line with standards set out under the UN Code of Conduct for Law Enforcement Officials and the Basic Principles on the Use of Force and Firearms by Law Enforcement Officials,” the statement said.