India and Pakistan agreed to an immediate ceasefire on Saturday, unexpectedly halting the worst fighting in decades between the nuclear-armed neighbors, just when their tit-for-tat strikes appeared to be spiraling out of control.

India and Pakistan traded accusations of ceasefire violations early Sunday, hours after US President Donald Trump announced that the nuclear-armed neighbors had stepped back from the brink of full-blown war.

The ceasefire had been expected to bring a swift end to weeks of escalating clashes triggered by the mass shooting of tourists last month that India blames on Pakistan.