Composite fracture (static or fatigue) involves fiber fracture and pull-out. The diagram below illustrates the effect of fiber fracture on the stress distribution in the composite matrix and fiber. When the fiber fractures, the load on the crack surfaces is zero and the bonding between the fiber and the matrix provides shear forces that load the fiber in tension away from the crack

The tensile stress in the fiber is, therefore , zero at the crack surface and increases along the fiber length due to the shear interaction with the matrix until there is no relative strain between the matrix and the fiber. The matrix has an increase in tensile stress in the region of the fiber crack as it accepts load to compensate for the broken fiber.
The photograph shows the stress pattern in a uniaxial matrix with broken fibers (light regions).

From: Hull, "An Introduction to Composite Materials," Cambridge (1992) and van Vlack, "Elements of Materials Science & Engineering,"
Addison Wesley (1989)