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1ES 1927+654 was known as a type 2 Seyfert galaxy, which exhibited drasticvariability recently in ultraviolet (UV)/optical and X-ray bands. An UV/opticaloutburst was observed in the end of 2017, and it reached the peak luminosity$\sim 50$ days later. The high-cadence observations showed a rapid X-ray fluxdecline with complete disappearance of the power-law hard X-ray component whenthe soft X-ray thermal emission reached its lowest level about $150$ days afterthe UV/optical peak. The power law X-ray component reappeared with thermalX-ray emission brightening from its lowest flux within next $\sim$ 100~days. Weassume an episodic accretion event taking place in the outer region of the discsurrounding a central black hole (BH), which is probably due to a red giantstar tidally disrupted by the BH. The inner thin disc with corona is completelyswept by the accretion event when the gas reaches the innermost circular stableorbit. The field threading the disrupted star is dragged inwards by the discformed after the tidal disruption event, which accelerates outflows from thedisc. The disc dimmed since a large fraction of the energy released in the discis tapped into the outflows. The accretion rate of the episodic accretion eventdeclines, and ultimately it turns out to be a thin disc, which is inefficientfor field advection, and the outflows are switched off. A thin disc with coronareappears later after the outburst.

An accretion disc with magnetic outflows triggered by a sudden mass accretion event in changing-look active galactic nucleus 1ES 1927+654