Rival militant organizations on both sides of the Afghanistan-Pakistan border have increasingly been teaming up in deadly raids, in what military and intelligence officials say is the insurgents’ latest attempt to regain the initiative after months of withering attacks from American and allied forces, The New York Times reports.

New intelligence assessments from the region assert that insurgent factions now are setting aside their historic rivalries to behave like “a syndicate,” joining forces in ways not seen before. After one recent attack on a remote base in eastern Afghanistan, a check of the enemy dead found evidence that the fighters were from three different factions, military officials said.

In the past, these insurgent groups have been seen as sharing ideology and inspiration, but sharing ideas and plans only sometimes.

Now the intelligence assessments offer evidence of a worrisome new trend in which extremist commanders and their insurgent organizations are coordinating attacks and even combining their foot soldiers into patchwork patrols sent to carry out specific raids.

The change reveals the resilience and flexibility of the militant groups. But at the same time, officials say, the unusual and expanding alliances suggest that the factions are under new military pressure. American and NATO officials say these decisions by insurgent leaders are the result of operations from American, Afghan and allied forces on one side of the border, and from the Pakistani military — and American drone strikes — on the other.

One official said it was “a wake-up call” to find evidence, after the attack on the forward operating base, that the fighters were partisans from three factions with long histories of feuding: the Quetta Shura Taliban of Mullah Omar; the network commanded by the Haqqani family; and fighters loyal to the Hekmatyar clan.

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