We report the discovery of attractive magnetic skyrmions and their clusters
in non-centrosymmetric ferromagnets. These three-dimensional solitons have been
predicted to exist in the cone phase of chiral ferromagnets (J. Phys: Condens.
Matter 28 (2016) 35LT01) and are fundamentally different from the more common
repulsive axisymmetric skyrmions that occur in the magnetically saturated
state. We present real-space images of these skyrmion clusters in thin (~70 nm)
single-crystal samples of Cu2OSeO3 taken using transmission electron
microscopy and develop a phenomenological theory describing this type of
skyrmion