The complaint came from Charles Davis, a retired police sergeant living in Kailua whose son's experience prompted him to send a letter to Mayor Jeremy Harris.

His son, 17-year-old Marc Davis, was working behind the counter at the Enchanted Lake Subway sandwich shop at about 10:15 p.m. when the robber entered, armed with a knife and what witnesses described as a "bomb-like device," a plastic box with wires attached.

He ordered the staff to open the register, and when they replied that they could not, he tried unsuccessfully to force it open.

The robber left, and the younger Davis called 911. He said he told the call taker that a robber had just fled and was placed on hold. He said he waited for 10 minutes, hung up and tried again, and then waited for another 10 minutes.

On the third call, he lodged a complaint with the dispatcher, and then called his father, who summoned police directly from the Kailua substation.

Maj. Karl Godsey, acting assistant police chief, said the problem is twofold. The Kapolei dispatch office, in use because of hurricane-proofing work being done at the downtown office, lacks the capacity to separate calls into urgent and non-emergency queues. At the main station, he said, callers with urgent cases are directed to the emergency queue, but at Kapolei, all calls wait on line together. That is a problem being addressed this week by phone company installation teams, he said.

He added that the call taker also should have spent more time sorting out the important cases; the danger here is that lengthy questioning also slows the answering of the phones.

"But if we were to be in that situation again, we might ask a couple more questions now," Godsey said.

The suspect in the robbery attempt is described as 18-20, 6 feet to 6 feet 2 inches tall, 140-160 pounds, with a medium build, olive complexion and long curly eyelashes. He was last seen wearing a gray, hooded jacket, black jeans and work shoes, and what was described as a SWAT-type scarf covering the lower portion of his face.