What program is used to add Motion Blur in 2D animation

Some animations make great use of motion blur

Here are some example in Space Dandy episode 2 fight scene, the use of motion blur is very clear and works perfectly giving the smooth effect

https://www.youtube.com/watch?v=zR0cx5BgPm0

Also in this short animation

https://www.youtube.com/watch?v=y6ZmMjMdrqs#t=226

I’ve looked at ‘the making of’ for those animations. They start off with roughs on paper/flash, then comes the line art, then the colours, and finally the composting.

But none mention the details, like what software or how. Any tutorials?

I don’t know for sure, but they may be using Adobe After Effects for motion blur.