Four from Planet 5 (1959)

The radio and television stations of the world carried the short, terrifying statement: The visitors were telepaths. These children from another time, another planet, were able to read human minds. They were utterly invincible. And they were infinitely dreaded... In the Pentagon and the Kremlin, leaders were grim with the awareness that all military secrets would be exposed... The overlords of the underworld realised that the children could smash their most profitable rackets... And even ordinary citizens shuddered at the prospect of their shabby sins being found out. So four small children came to be hated by the world. A whole civilisation wanted them dead.