Unknown caterpillar?

Unknown caterpillar?

Observation - Unknown caterpillar? - UK and Ireland. Description: Crossing cut grass lawn at front of house. 95 - 100 mm in length. Dark brown animal with dark eye markings on both sides. body tapering towards head end, paler and moving around from side to side. Two sets of legs, one shorter number at front end, more

Crossing cut grass lawn at front of house.
95 - 100 mm in length.
Dark brown animal with dark eye markings on both sides. body tapering towards head end, paler and moving around from side to side. Two sets of legs, one shorter number at front end, more numerous at body towards tail end. Moves rapidly, hence blurring on one picture.