MPs on the Culture, Media and Sport Select Committee are set to call bosses from Twitter to answer questions about abusive tweets and their response to the issue.
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A picture of Cecil the lion - the animal killed by an American dentist in Zimbabwe - has been projected on to the Empire State Building.
A man, believed to be in his 50s, was pronounced dead at the scene after apparently suffering a heart attack.
A healthy retired nurse has ended her life at a Swiss suicide clinic because she did not want to become old.