HONOLULU -- Honolulu police officials admit that a technical failure, and not human error, is most likely to blame for problems with its 911 system Tuesday during a test of the department's back-up communications system.

The emergency system cut off hundreds of callers seeking police assistance when dispatchers worked out of the brand-new Alternate Communications Center in Kapolei between 6 a.m. and 6 p.m. The calls were being cut off as they were being transferred from the main dispatch center at the main police headquarters to the Kapolei center.

Initially, HPD communications division commander Maj. Scott Foster had said the cut-offs were operator errors.

"It turned out that there was a human error in the transfer of the calls," he said Wednesday.

Foster apologized for those comments Friday, after officials found that a software glitch or other technical problem caused the problem, not the operators. Verizon Hawaii, the company that built the system, said that it is investigating the errors.

"At this point, we don't know exactly what the problems were that day," Verizon spokeswoman Ann Nishida said. "We are looking into it. We are testing equipment and what we need to do right now is to actually test each piece of equipment, one by one."

Police also initially downplayed the problem, saying Wednesday that between 40-50 calls were disconnected. Officials acknowledged Friday that 75-100 callers were cut off.

But 911 operators and police dispatchers who worked that day told KITV4 News that the problem was much worse than that, estimating that hundreds of callers were disconnected before they could begin speaking to police dispatchers. Verizon said Friday that its system doesn't record the number of disconnected calls.

"Kapolei is on a basic 911 system, which doesn't provide all the data that the normal enhanced 911 system would," Nishida said.

Honolulu City Councilman John Henry Felix, chairman of the public safety committee, said that he hopes to call police and Verizon officials before this committee next Tuesday in an effort to find what went wrong.