Production of ionospheric 1-m irregularities in the auroral zone E region by high power ionospheric heating has been observed by means of the STARE auroral radar. Irregularities were produced at night, on eight occasions by using an O mode heating wave and on two occasions by using an X mode heating wave. The growth time of the irregularities is found to be approximately 30 s. Several physical possibilities to explain these findings are discussed, and mechanism is suggested that is closely related to Sato's mechanism of quiet auroral arc formation.