title: Regular expression to extract number before/after word
body: <p>I have <code>10000</code> descriptions and I want to use regular expressions to extract the number associated with the phrase ``arrested''.</p>
  
  <p>For example:</p>
  
  <pre><code>"police arrests 4 people"
  "7 people were arrested". 
  </code></pre>
  
  <p>The numbers range from <code>1-99</code>.</p>
  
  <p>I have tried the following code: </p>
  
  <pre><code>gen arrest= regexm(description, "(^[1-9][0-9]$)[ ]*(arrests|arrested)")
  </code></pre>
  
  <p>I cannot simply extract just the number, because the descriptions also mention numbers that have nothing to do with arrests.</p>