We present the results of optical ( R band ) photometric and polarimetric monitoring and Very Long Baseline Array ( VLBA ) imaging of the blazar ( catalog S5~0716+714 ) along with Fermi \gamma -ray data during a multi-waveband outburst in 2011 October .
We analyze total and polarized intensity images of the blazar obtained with the VLBA at 43 GHz during and after the outburst .
Monotonic rotation of the linear polarization vector at a rate of \gtrsim 50 \arcdeg per night coincided with a sharp maximum in \gamma -ray and optical flux .
At the same time , within the uncertainties , a new superluminal knot appeared , with an apparent speed of 21 \pm 2 \leavevmode \nobreak c .
The general multi-frequency behavior of the outburst can be explained within the framework of a shock wave propagating along a helical path in the blazar ’ s jet .