article_snippet: Armed and dangerous: Campbell is described as unstable and mentally disturbed.
article_snippet: Anyone who encounters Campbell is urged to call police .
article_snippet: Local authorities have issued a nationwide alert to help locate Patrick Campbell, who is considered armed and dangerous.
article_snippet: Anyone who recognizes him is asked to call police right away, as the 27-year-old is believed to be unstable.
highlights_snippet: Campbell is considered mentally unstable and anyone who encounters Campbell should call police .