Portuguese police are dropping their investigation into the disappearance of British child Madeleine McCann due to a lack of evidence, media reported Tuesday. Three Portuguese newspapers said the Public Prosecutor's office would call off its search for the girl before August 15, when the customary official secrecy period covering the investigation ends. Closing the case would mean that official suspects, including Madeleine's parents, would no longer be under formal investigation. Police could reopen the case if new evidence were to emerge, the newspapers said. The three - Correio da Manha, Jornal de Noticias and Expresso - cited unidentified police sources saying the 14-month investigation had reached a dead end.