Police in Lancashire are hunting a man from Chorley who posted "sick" comments about missing schoolgirl April Jones online.
His comments sparked an angry backlash on Facebook.
A vigilante group is reported to have called at the man's parents' house in Chorley.
Lancashire Police confirmed it was investigating the comments and was looking for a man in connection with their inquiry.
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Much of the rest of this week is looking very changeable, cool and windy with showers or longer spells of rain
Windy on Tuesday evening, gusts of 45-50mph at the coast. Unsettled for the next few days, rain never far away
Provisional figures show that April 2015 has been the sunniest in Met Office UK records dating back to 1929 with 212 hours of sunshine