  We report the detection of GeV gamma-ray emission from the molecular cloud
complex that surrounds the supernova remnant (SNR) W44 using the Large Area
Telescope (LAT) onboard Fermi. While the previously reported gamma-ray emission
from SNR W44 is likely to arise from the dense radio-emitting filaments within
the remnant, the gamma-ray emission that appears to come from the surrounding
molecular cloud complex can be ascribed to the cosmic rays (CRs) that have
escaped from W44. The non-detection of synchrotron radio emission associated
with the molecular cloud complex suggests the decay of neutral pi mesons
produced in hadronic collisions as the gamma-ray emission mechanism. The total
kinetic energy channeled into the escaping CRs is estimated to be
(0.3--3)x10^{50} erg, in broad agreement with the conjecture that SNRs are the
main sources of Galactic CRs.
