The top senators on the Senate Judiciary Committee are requesting that federal investigators look into claims of abuse of immigrants held at government-run detention facilities.

Sens. Chuck Grassley (R-Iowa) and Dianne Feinstein (D-Calif.) made the request on Monday night, saying media reports on the alleged abuse indicate "a long-term pattern" of mistreatment.

"These allegations of abuse are extremely disturbing and must be addressed," Grassley and Feinstein wrote. "This is not a partisan issue as reporting suggests many have been occurring for years. Immigrant families and children kept in federal custody deserve to be treated with basic human dignity and respect and should never be subjected to these forms of abuse."

The Associated Press first reported the letter.

The senators are calling for the inspectors general at the departments of Homeland Security (DHS) and Health and Human Services (HHS) to immediately launch an investigation into the claims of physical, sexual and emotional abuse.

Feinstein and Grassley also requested that investigators look at "the adequacy of policies and procedures" used by U.S. Immigration Customs Enforcement (ICE) and HHS to prevent abuse.

DHS spokeswoman Katie Waldman told the AP that officials perform their duties "professionally and humanely" and that the agency "is abiding by the intent and letter of law and maintains the highest standards [of] care for individuals in our custody."

She added that DHS facilities "undergo constant unannounced inspections by outside groups, the department's inspector general and court-ordered monitors."

"HHS will comply with the request for an investigation into the abuse allegations, as it is our longstanding agency practice to cooperate with the IG on any investigation," HHS spokeswoman Evelyn Stauffer told The Hill.

Several media outlets have reported claims of abuse at immigrant detention facilities, including an AP report last month that children at a facility in Virginia alleged they were beaten while in handcuffs and left naked and cold in cells.

The New York Times also reported this month that two female migrants said they were sexually assaulted at detention centers in Pennsylvania and Texas.

The Trump administration has faced scrutiny over the detention of immigrants after a since-ended policy mandated the separation of immigrant children from their families at the border. Trump signed an executive order last month to end the policy.

- Updated at 10:51 a.m.