GAZA — Shortly before midnight, seven black-masked young men in camouflage stood in a field of waist-high weeds, Kalashnikov rifles pointed toward the Mediterranean Sea a half-mile away.

No Israeli soldier has set foot in Gaza City in five years, but the 25-year-old commander of this band of Al-Quds Brigades — the armed wing of Islamic Jihad — said his troops stand vigil here nightly to “protect the Palestinian people” from any “incursion.” Every few minutes, in what may have been a nightly ritual or an effort to broadcast to the world their readiness to fight, the radio on the commander’s shoulder crackled with warnings: drones in the east, F-16s overhead, gunboat movement at sea.

“You are the men; you, the Al-Quds Brigades, are the real men,” the voice said after reciting verses from the Quran praising jihadist militants and martyrs. “God protect you in the field.”

Smaller and less known internationally than the militant Islamic Hamas faction that has ruled since 2007, Islamic Jihad and its Al-Quds Brigades are having something of a renaissance. Last month the group captured global headlines by firing a barrage of 100 rockets toward Israel in less than an hour. Polls show that support for Islamic Jihad among residents of Gaza remains far below that of the leading political factions but has seen an uptick as the group has lately built health clinics, opened schools, and expanded its family-mediation services.