A woman and her four children escaped a house fire at 1113 Cypress in Port Huron with no injuries.  Firefighters were called to the scene shortly before 10:00 p.m. last evening.  According to reports by the Port Huron Fire Department the blaze appeared to have started in a microwave oven.  The oven was removed from the inside of the house to an outdoor porch area where it caught the exterior of the home on fire.  The building suffered smoke damage in the rear of the home and fire damage to the exterior.  Authorities believe the fire was accidental.