US intelligence officials have “high confidence” that an explosion at a Gaza hospital last week was caused by a Palestinian rocket that broke up mid-flight, and not by Israel, a US official said, Reuters reports.

The New York Times, NBC News and other US media reported the US intelligence assessment earlier on Tuesday, citing a briefing with reporters. The US official declined to be named as the information remained confidential.

The officials said there was still uncertainty around the death toll and the number of injuries, the New York Times reported. The officials said there was little damage to the hospital and the structure did not collapse, it reported.

The intelligence assessment was based on Israeli intercepts of Palestinian groups, publicly available video, communications intercepts provided by the Israelis and images of the blast and the aftermath, the officials told the newspaper.

An unclassified US intelligence report seen by Reuters two days after the blast estimated the death toll was “probably at the low end of the 100 to 300 spectrum” but added that the assessment may evolve.