Many mobile phones in use today feature easier access to emergency numbers, so accidentally dialling 911 is more likely. ((Eric Risberg/Associated Press))

Ottawa police say they received more than 23,000 unintentional 911 calls in 2009 and a growing number are coming from mobile phones tumbling inside pockets and purses.

About 11 per cent of the more than 230,000 emergency calls in Ottawa in 2009 were either hang-ups or mistakes. But while a mistaken call can quickly be determined by asking the caller a series of questions, police said hang-ups require followup.

"The best thing you can do to help us ascertain whether this is an actual call or an emergency is to stay on the line," said Staff Sgt. Sandra McLaren. And if police call you back, answer the phone, she said.

"Don't be embarrassed. We realize with cellphone technology today it can be very simple for a false 911 call to occur," she said.

Police services across the country are reporting an increase in "pocket dialing."

Alex Montenegrino, a salesman at Future Shop, said some phones are more susceptible to pocket dialing than others, but anyone can take precautions to prevent unwanted dialing.

"The best thing to do regarding pocket dialing is get yourself a good case and always lock your phone," said Montenegrino. 

Police also advise against putting 911 on a phone's speed dial.