Democratic senators led by Kirsten Gillibrand urged President Donald Trump's administration on Monday to release within one week the results of a US military probe into a February 28 attack on a girls' school in Iran.

Reuters initially reported on March 5 that an early internal US military review indicated American forces were probably behind the deadly strike in Minab on the first day of the conflict with Iran.

More than two dozen senators, including Senate Armed Services Committee ranking member Jack Reed, called for the military to complete its review, inform Congress, and outline steps to avoid similar errors in the future.

"There is no justification for withholding an unclassified accounting of what happened, what went wrong, and what the Department is doing to prevent recurrence," the letter stated.

A Pentagon official responding to Reuters noted: "The investigation is ongoing. We do not have any updates to announce at this time."

Senators Push for Probe Findings Release

The attack claimed the lives of more than 175 children and teachers, according to Iranian officials. The senators' letter highlights that this would represent the US military's deadliest civilian incident since 1991, when a mistaken bombing of a shelter in Iraq killed over 400 people.

Archived versions of the school's website indicate it sits next to a facility run by the Islamic Revolutionary Guard Corps, the force answering to Iran's supreme leader.

Reuters, drawing on sources close to the matter, reported that US officials preparing targeting data appeared to rely on outdated intelligence.

US Admiral Brad Cooper, who leads Central Command overseeing the war, stated in May that the probe was "complex" because the school stood on an active Iranian cruise missile base.

Trump has questioned whether the military can ever determine the cause amid heavy fighting at the war's outset.

"Somebody said it was our missile, maybe it wasn't our missile, but I have seen nothing to lead me to believe it was," Trump said on June 24, adding: "I don't think it was us."

Iranian officials have labeled the school strike a US war crime. The US has said it never intentionally targets civilians.

Probe Focuses on Fatal School Attack

In their letter, the lawmakers call on Cooper and Defense Secretary Pete Hegseth to provide an unclassified summary of the findings to Congress and the public. They also request a prevention and remediation plan "that identifies the specific corrective actions the Department will take to ensure this does not happen again."

"The United States military has a legal and moral obligation to take all feasible precautions to prevent civilian harm," the letter said.

"When a US strike kills civilians, the Department owes Congress, the American people, and the victims' families a clear accounting of what happened and a credible plan to prevent future failures."