Washington: An ongoing military investigation has determined that the United States is responsible for a deadly Tomahawk missile strike on an Iranian elementary school, according to US officials and others familiar with the preliminary findings. The February 28 strike on the Shajarah Tayyebeh elementary school building was the result of a targeting mistake by the US military, which was conducting strikes on an adjacent Iranian base of which the school building was formerly a part, the preliminary investigation found. Officers at US Central Command (CENTCOM) created the target coordinates for the strike using outdated data provided by the Defence Intelligence Agency (DIA), people briefed on the investigation said. Officials emphasised that the findings are preliminary and that there are important unanswered questions about why the outdated information had not been double-checked. Striking a school full of children is sure to be recorded as one of the most devastating single military errors in recent decades.…