British policeman killed investigating burglary, PM Johnson shocked

British police launched a murder investigation after an officerwas killed in southeast England, the latest in a spate of violent crimes that has forced new Prime Minister Boris Johnson to pledge to do more to protect law and order.Police said on Friday that constable Andrew Harper was killed while attending a reported burglary late on Thursday near a major road.Ten males aged between 13 and 30 have been arrested on suspicion of murder.