  We study a sequence of eruptive events including filament eruption, a GOES
C4.3 flare and a coronal mass ejection. We aim to identify the possible
trigger(s) and precursor(s) of the filament destabilisation; investigate flare
kernel characteristics; flare ribbons/kernels formation and evolution; study
the interrelation of the filament-eruption/flare/coronal-mass-ejection
phenomena as part of the integral active-region magnetic field configuration;
determine H\alpha\ line profile evolution during the eruptive phenomena.
Multi-instrument observations are analysed including H\alpha\ line profiles,
speckle images at H\alpha-0.8 \AA\ and H\alpha+0.8 \AA\ from IBIS at DST/NSO,
EUV images and magnetograms from the SDO, coronagraph images from STEREO and
the X-ray flux observations from FERMI and GOES. We establish that the filament
destabilisation and eruption are the main trigger for the flaring activity. A
surge-like event with a circular ribbon in one of the filament footpoints is
determined as the possible trigger of the filament destabilisation. Plasma
draining in this footpoint is identified as the precursor for the filament
eruption. A magnetic flux emergence prior to the filament destabilisation
followed by a high rate of flux cancelation of 1.34$\times10^{16}$ Mx s$^{-1}$
is found during the flare activity. The flare X-ray lightcurves reveal three
phases that are found to be associated with three different ribbons occurring
consecutively. A kernel from each ribbon is selected and analysed. The kernel
lightcurves and H alpha line profiles reveal that the emission increase in the
line centre is stronger than that in the line wings. A delay of around 5-6 mins
is found between the increase in the line centre and the occurrence of red
asymmetry. Only red asymmetry is observed in the ribbons during the impulsive
phases. Blue asymmetry is only associated with the dynamic filament.
