The phone rang twice before the police officer picked it up.
'Help!' came the woman's voice at the other end of the line. 'There's a robber running down my street. He came out of the bank opposite my house'.
'OK, so you're a witness to a crime, madam, I see,' said the policeman slowly. ' Now, has this robber got a weapon?'
'Yes, yes, he's got a gun'.
"Right, madam, I'll send my best detective immediately.