The deadly US strike on a girls school in the Iranian coastal city of Minab happened due to gaps in the Pentagon’s system for analyzing potential targets, Bloomberg has reported, citing people familiar with the investigation.

The bombing, in which more than 120 students aged between 6 and 13 were killed in addition to 26 teachers, happened on February 28, the opening day of the American-Israeli military campaign against Iran.

The investigation into the incident, ordered by the chief of US Central Command (CENTCOM) Brad Cooper, was completed in April, but its results haven’t yet been made public, Bloomberg said in an article on Friday.

According to its sources, the probe found that in 2019 a US intelligence analyst, who was examining information about potential targets inside Iran, discovered that a site in Minab that had been previously designated as a naval facility used by Iran’s Islamic Revolutionary Guard Corps (IRGC) was actually an elementary school, the agency’s sources claimed.

However, the update ended up being missed by his higher ups and never reached the US military commanders because the analyst made it using a digital intelligence tool that wasn’t connected to the official intelligence database that the Pentagon relies on to prepare its strikes, they said.

The people familiar with the matter told the agency there are “significant and longstanding gaps” in the Pentagon’s system for analyzing potential targets.

At least two intelligence databases used for inputting remarks by analysts, working with imagery, have not been linked to the official and authoritative database used during bombing raids, they said.

US President Donald Trump said on Wednesday that the actual culprit behind the strike in Minab may never be established.

“There were missiles flying all over the place, and it’s horrible what happened… 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.

During a debate at the UN in late March, Iranian Foreign Minister Abbas Araghchi said that the girls school had come under a “calculated, phased assault.” He called the attack “a war crime and a crime against humanity, one that demands unequivocal condemnation by all, and unambiguous accountability for the culprits.”

The head of Airwars NGO, Emily Tripp, told Bloomberg that her organization tracked some 300 incidents of civilian harm in Iran during the conflict, but stressed that it was difficult to establish if the US or Israel was responsible for them.