Flying Fortresses of the Eighth Air Force struck in force yesterday at Bremen, great North Sea port which harbors Germany's long-range U-boats and industrial center which includes the biggest of the Focke-Wulf assembling plants.
    The bombers, escorted part of the way by Thunderbolts, delivered the third American daylight blow at the port this year.
    At a late hour last night no further details of the mission had been announced by Eighth Air Force headquarters. German news agency said: "In the center of Bremen there was large-scale destruction in residential quarters and damage was done to public buildings and cultural monuments."
    The raid followed by less than 12 hours an RAF night assault on Stuttgart, in southern Germany, whose big manufacturing plants specialize in aircraft and tank engines and electrical and precision machinery.
    The RAF bombers roared away from England on their mission even while German bombers were delivering a weak retaliatory attack on southeast England and London. An estimated 15 raiders reached London, and residents of the city, as well as American soldiers there, witnessed a thundering demonstration of the capital's anti-aircraft defenses.
    In addition to Stuttgart, the RAF bomber fleets hit Friedrichshafen and Munich on a smaller scale. From all operations seven RAF planes were missing.
    Friedrichshafen, hit by Lancasters, is the site of Germany's big radiolocation plant and situated on Lake Constance, across from Switzerland. It was last bombed by the RAF on the famous shuttle raid to Africa May 29.
    The Air Ministry reported that clouds prevented full observation of results in the attack on Stuttgart.
    It was the RAF's fifth major raid on German cities since the start of the month.
    In the American raid, though no details were available officially last night, it was reported that the Fortresses and P47 escorts shot down a large number of enemy interceptors.
    Returning crewmen said the flak encountered over Bremen was some of the heaviest yet experienced.
    Berlin radio last night admitted that considerable damage was caused in the Fortress raid on Bremen.
    "Strong forces of enemy bombers carried out a terror attack on another northern German coastal area this afternoon," said the radio. "Considerable destruction was caused, particularly in the town of Bremen.
    "Damage was done to residential quarters as well as to public buildings and cultural monuments. The population suffered casualties."

    The largest formations of Eighth Air Force heavy bombers ever dispatched from Britain bombed Bremen and operated over northern France Friday and left the great German inland port "well plastered" in spite of heavy anti-aircraft.
    Fifty-six enemy fighters were destroyed -- 36 of them by escorting Thunderbolts and Lightnings -- for a new combat record, topping their previous high mark of 25 destroyed July 30 on the Kassel raid. Twenty-nine heavy bombers, four mediums and five fighters were lost.
    Bomber crews who went to Bremen, a major shipbuilding port which is the largest producer of 750 and 1,200-ton Nazi submarines, reported good bombing results, but one force of Fortresses which went to France found its target covered by clouds and returned without dropping bombs. A standing order forbids indiscriminate bombing in the occupied countries.
    In spite of Lightning and Thunderbolt escort over the target, some of the Fortress and Liberator formations which struck at Bremen encountered persistent attacks by as many as 100 German fighter planes. The raiders met an intense ack-ack barrage over the target.
    While the heavies hammered Bremen Marauders ripped up airfields in the Pas de Calais area of northern France. Crews reported good bombing and "lots of smoke and destruction."
    It was "colder than hell" flying over Germany. 2/Lt. Bayard T. G. Dudley, of Houston, Tex., co-pilot of Ritzy Ritz, said the thermometer in his cockpit "went down to 48 degrees below zero; then the needle hit the peg and started to bend."
    Two ball turret doors ripped off in the wind. One of the gunners, Sgt. Charles S. Bullions, of Mount Lebanon, Pa., crawled up into the plane and rode as a passenger the rest of the way, but the other, Sgt. Robert Dearth, of Columbus, Ohio, stuck it out in his open turret, despite the subzero gale, until after the bombs were dropped. It was 19-year-old Dearth's first mission.