SAN DIEGO (CBS 8) - A 911 caller says they were on hold for ten minutes with San Diego Police dispatchers while an armed robber hit a La Jolla restaurant and escaped earlier this month.

The robbery took place at around 9 p.m. on Monday, May 9th at the Chedi Thai Bistro on Pearl Street near Eads Avenue. The gun-wielding robber was first seen casing the business just before breaking through the back door of the restaurant. A nearby business called the San Diego Police Non-Emergency line to report the suspicious man. The caller, who has chosen to remain anonymous, says he was on hold for nearly ten minutes.

While he was on hold, the armed robber burst through the rear of the restaurant and robbed the employees at gunpoint. The owner of the restaurant says she called 911 and that she too was put on hold.

"I called three times and it took ten minutes to have someone answer the phone," said Pia, owner of Chedi Thai Bistro. 

A spokesperson for the police department says that a call was made to the non-emergency line before the robbery took place about a suspicious man and that they placed that caller on hold for four minutes because officers were tied up with other calls. During the robbery, the spokesperson confirms that a second person called 911 during the time of the robbery and was placed on hold for 40 seconds, but the caller hung up. The caller called back again and was placed on hold for an additional 17 seconds.

"It was very frustrating," said Pia.

Recently, 911 hold times have been an issue for the City of San Diego. In April, an infant died when the family dog became spooked and bit the newborn. The parents say they called 911 twice, but they were unable to get thRough. 

RELATED: Autopsy: Newborn killed by dog died of bites to head

"We have put a lot of measures in place to make sure that we are more efficient," said San Diego Police Chief Shelley Zimmerman. 

Chief Zimmerman says that since the death of the newborn in April, the department has hired an additional three dispatchers. The department says they still have 18 vacancies to fill. 

RELATED: Mayor Faulconer discusses 911 dispatch issues

Police have described the robbery suspect as a black male in his 20's, about 5 feet and 160 pounds with curly hair. If you have any information about this robbery, you are asked to contact the San Diego Police Department