Use energy weapons. Roast the invaders alive in their vehicles.
https://en.wikipedia.org/wiki/Directed-energy_weapon
D0%97%D0%B1%D1%80%D0%BE%D1%8F_%D1%81%D0%BF%D1%80%D1%8F%D0%BC%D0%BE%D0%B2%D0%B0%D0%BD%D0%BE%D1%97_%D0%B5%D0%BD%D0%B5%D1%80%D0%B3%D1%96%D1%97">https://uk.wikipedia.org/wikiD0%97%D0%B1%D1%80%D0%BE%D1%8F_%D1%81%D0%BF%D1%80%D1%8F%D0%BC%D0%BE%D0%B2%D0%B0%D0%BD%D0%BE%D1%97_%D0%B5%D0%BD%D0%B5%D1%80%D0%B3%D1%96%D1%97