Fire a few missiles at them and see what happens.....
That has been done. Interceptor aircraft have also fired upon them. No hits. There was an F-89 Scorpion that fired on one in the 1950s. The “swamp gas” shot the Scorpion down. In general, governments all of the word came to the conclusion that the “swamp gas” was mostly harmless, but it was probably a good idea to ignore them with malice.