According to reports, the Ukrainian military is attempting to disable the Russian S-400 air defence system with an AGM-88 anti-radiation missile that was given by the US.

With AGM-88 HARM missiles, the Ukrainian military has attempted to disable anti-aircraft radars on missile systems. S-400 and Buk-M3 in Kherson and Nova Kakhovka.
an AGM-88 missile that was supposed to hit a certain location on the S-400 instead struck an apartment complex in the Kherson neighbourhood. The reports claim that because the residential structure wasn’t the planned target, the missile may have malfunctioned or perhaps been intercepted.

It’s possible that the Russian air defence system’s control unit saw an AGM-88 missile approaching and shut off the radar as a result. The missile can be identified by the S-400’s VVO 96L6 system, the Buk-M3 complex’s 9S18M3 Kupol radar, or even the Gazetchik-E complex, which is built to safeguard ground radars. . Additionally, Russian R-330ZH Zhitel or R-330M1P electronic suppression complexes may have caused the AGM-88’s systems to malfunction, making the AGM-88 an undetectable targeted assault.
Such anti-radiation attacks would become more frequent, and Ukrainian forces would probably launch a lot of AGM-88 missiles to attack Russian air defences heavily.
The Tor-M2U self-propelled air defence system, however, might be the best tool for dealing with such a danger. Each 9A331M Tor-M2U combat vehicle is capable of shooting down at least 6–8 HARM missiles, according to estimates.