  Recent James Webb Space Telescope (JWST) observations have revealed a
surprisingly abundant population of faint, dusty active galactic nuclei (AGNs)
at z~4-7. Together with the presence of supermassive black holes (SMBHs) at
z>6, this raises questions about the formation and growth histories of early
black holes. Current theories for the formation of seed black holes from the
death of the first stars (i.e. light seeds) and/or the direct collapse of
primordial gas clouds (i.e. heavy seeds) still lack observational confirmation.
Here, we present LID-568, a low-mass (7.2e6Msun) black hole hosting powerful
outflows that is observed in an extreme phase of rapid growth at z~4. This
object is similar to other JWST-discovered faint AGN populations, but is bright
in X-ray emission and accreting at more than 4000% of the limit at which
radiation pressure exceeds the force of gravitational attraction of the black
hole (i.e. super-Eddington accretion). Analysis of JWST NIRSpec/IFU data
reveals spatially extended Ha emission with velocities of ~ -600 - -500 km/s
relative to the central black hole, indicative of robust nuclear-driven
outflows. LID-568 represents an elusive low-mass black hole experiencing
super-Eddington accretion as invoked by models of early black hole formation.
This discovery showcases a previously undiscovered key parameter space and
offers crucial insights into rapid black hole growth mechanisms in the early
universe.
