LONDON, Friday--The German Gestapo, launching a wave of Czech executions in reprisal for the attempted assassination of Reinhard Heydrich, has slain six members of a single family, including two women, the Nazi-controlled Prague radio announced today.

Ominously the broadcast said the vengeance executions had "started," implying that the former republic of Czechoslovakia was in for a blood bath because of the attack on Heydrich, "the hangman" and deputy leader of the Gestapo, who admittedly was in a grave condition.

The first six victims were accused of concealing a "person known to be engaged in activities against the Reich." In addition to the two women, they included a youth of 17.