More than 50 Republican lawmakers are urging acting Attorney General Todd Blanche to launch a federal investigation into the deaths of five babies whose remains were recovered from a Washington, D.C., abortion clinic in 2022, arguing the case has gone unexamined for years, the Daily Wire reported on Tuesday.

Led by Sen. Mike Lee, R-Utah, and Rep. Chris Smith, R-N.J., the lawmakers called on Blanche to "comprehensively investigate the circumstances surrounding the deaths of five preborn children" recovered by the Metropolitan Police Department from the Washington Surgi-Clinic, formerly operated by late-term abortion provider Dr. Cesare Santangelo.

In a letter sent Tuesday, the lawmakers said they want the Justice Department to determine whether the babies were victims of illegal infanticide or violations of the federal Partial-Birth Abortion Ban Act.

"For four years, members of Congress have remained alarmed at this clear violation of life and law, but the Biden Administration Department of Justice refused to act," the lawmakers wrote, adding that the remains are still in the custody of D.C.'s Office of the Chief Medical Examiner.

The letter asks Blanche to order a "thorough investigation into the death of each child" — including autopsies, preservation of evidence, and an examination of whether federal criminal laws were violated.

The lawmakers also urged the Justice Department to ensure the infants receive a proper burial.

"We cannot undo the grievous, barbaric acts that killed these children in their most vulnerable stage, but we equally cannot allow such lawlessness and inhumanity to evade our justice system any longer," the letter states. "Under President [Donald] Trump's and your leadership, we are hopeful that these children will finally receive the justice they deserve."

The Justice Department confirmed receipt of the correspondence.

"We have received the letter and are ensuring the appropriate personnel within the department are reviewing it carefully," a department spokesperson said.

The renewed push comes as Blanche, who has served as acting attorney general since April, seeks Senate confirmation to permanently lead the Justice Department, the Daily Wire reported.

Several signatories to the letter — including Sen. Chuck Grassley, R-Iowa; Sen. Ted Cruz, R-Texas; Sen. Josh Hawley, R-Mo.; and Sen. Lee — serve on the Senate Judiciary Committee, which is expected to vote on Blanche's nomination in the coming days.

The case dates to March 2022, when pro-life activists Lauren Handy and Terrisa Bukovinac turned fetal remains they said they obtained outside the Washington Surgi-Clinic in Washington's Foggy Bottom neighborhood over to police.

Five of the recovered babies later became the focus of demands for further investigation by Republican lawmakers and anti-abortion advocates.

Pro-life physicians who reviewed photographs of the remains in 2022 concluded that several of the babies appeared to have been aborted late in pregnancy.

They argued one infant may have shown injuries consistent with a procedure prohibited under the federal Partial-Birth Abortion Ban Act, though those conclusions have not been confirmed by federal investigators or the D.C. medical examiner.

The lawmakers cited those medical opinions in their letter, noting estimates that one infant was between 28 and 32 weeks gestation and another appeared to be near full term.

Lee and Smith first requested an investigation from then-Attorney General Merrick Garland in 2022 but say the Justice Department never responded or opened a federal inquiry.

Instead, they wrote, reports later indicated the department advised the D.C. medical examiner's office to dispose of the remains before members of Congress intervened and urged officials to preserve the evidence.

Federal authorities have never publicly announced a criminal investigation into the deaths, and no federal charges related to the five babies have been filed. The Washington, D.C., medical examiner has not publicly released autopsy findings or a determination regarding the cause or manner of the infants' deaths.