Six others have been injured.
The policemen were killed when the convoy in which they were going was hit by a landmine planted by the Naxals.
The injured police personnel have been shifted to hospital. Senior police officials in Jharkhand informed OneIndia that the convoy was targetted by a landmine which the Naxals had planted.
Palamu in Jharkhand is known for its Naxal menace.
There had been intelligence suggesting that the Naxals may stage an attack in the event of a major operation undertaken against them by the security forces.