Police officers fired more than 600 rounds during an hourlong chase of three armed suspects in a bank robbery last year in Stockton, Calif. — which an independent review has concluded was "excessive and unnecessary."

The findings released by the nonprofit Police Foundation on Monday described a chaotic ordeal with "very little control" that contributed to the accidental death of one of three hostages, Misty Holt-Singh, who was shot by officers trying to save her. Two of the suspects also died. A third suspect survived without being shot "most likely because he used Holt-Singh as a shield," the report stated.

As the Two-Way blog reported at the time of the incident, two other hostages survived and the police chase didn't end until officers shot out the tires of the getaway vehicle.

The Associated Press reports that the lone surviving suspect remains in police custody:

"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."

In the report, titled "A Heist Gone Bad," Police Foundation President Jim Bueermann acknowledged the complexity of the situation:

"At first blush, it is easy to criticize the tactics of the Stockton Police Department (SPD) after 33 officers, at four different locations, fired more than 600 times into a getaway car carrying three bank robbers.They killed two of the bank robbers but also took the life of an innocent woman who had been held hostage. Like most things in this complicated world of ours, nothing is ever simple."

The report chronicles that the suspects fired 100-plus rounds at officers using an AK-47 assault rifle. Some 14 police vehicles were disarmed. But the lack of police planning in how to contain the incident contributed to the uncertainty:

"Officers were told not to shoot at the moving vehicle, which is part of the department's policy. So the officers kept pursuing. Obviously, there was no other choice. But it also meant there were long periods of uncertainty, leaving even the most experienced officers frustrated."

It also shed light on officers engaging in "sympathetic fire":

"Dozens of officers fanned out, many of them opening fire. There were no dedicated shooters. There was very little control. Just police officers trying to stop a threat. The gunfire roared as more than 600 shots were fired. In some cases, officers inexplicably opened fire with their colleagues standing in front of them. One officer lay prone on the ground, searching for a target but not seeing any. At the same time, a colleague standing above him fired off shot after shot. 'What's your target?' the prone officer yelled, thinking he was missing something. 'The car!' responded the officer, who continued shooting."

The Los Angeles Times reports:

"Stockton Police Chief Eric Jones, who called for the independent review, held a news conference Monday to discuss the findings." 'We said we'll accept responsibility, and that's what I'm doing here today,' Jones said. 'There's not a man or woman in the Stockton Police Department that does not wish it had a different outcome.' "

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