STOCKTON, Calif. — The 600 shots police fired at the chaotic end to a California bank robbery that claimed the life of a hostage were excessive, with some officers only firing their weapons because other officers were shooting, according to a report released Monday.

The report by the nonprofit Police Foundation also found some Stockton police officers opened fire with their colleagues standing right in front of them, and said a lack of planning was partly to blame for the unnecessary shooting.

“In reviewing dispatch tapes and in response to interviews, the review team determined there was no planned response for when the suspect vehicle stopped,” the report concluded. “This lack of planning, along with the number of officers involved, created a level of chaos that was difficult to manage and overcome.”

The July 2014 shootout left two suspects and a hostage, Misty Holt-Singh, dead. Police have said Holt-Singh, 41, was struck by 10 of the bullets officers fired as she was used as a human shield by the sole surviving suspect, Jaime Ramos. Ramos has been charged with three counts of murder in addition to robbery, kidnapping, carjacking and gang counts. He has pleaded not guilty.

Stockton police had requested the review by the Police Foundation. Police Chief Eric Jones said in a statement the department intends to learn everything it can from the report and use it to improve.

“There are elements of this report that are tough for us to read,” he said.