Killer

The police arrest Fred West and they take him down to the cells to interrogate him.

They say, "Right you evil f*cker how many have you killed?"

Fred says, "Seventeen."

So the coppers spend weeks digging up his house and find 25 bodies.

They go back to Fred and say, "You lyin' bastard you told us you only killed 17 but we found 25 bodies."

Fred says, "That's right, but I'm a builder and the first figure was only an estimate."