On the night of 1 to 2 May 1945, Major LaPrairie's company of the Irish Regiment of Canada carried out a night attack on the village of Weiwerd, the main strongpoint in the eastern defenses of the harbor of Delfzijl. With great skill, Major LaPrairie led his company to the edge of the village and launched an attack that took the Germans completely by surprise. Major LaPrairie realized that the only way for the Germans to escape the village was via a bridge across the Weiwerdermaar and urged his troops to push on quickly. They quickly made their way through the center of town and captured the bridge intact. LaPrairie immediately organized his company's positions to protect the bridge, which he knew would be invaluable in the final assault on Delfzijl.

With the main enemy forces on the west side of the Weiwerdermaar, less than a thousand yards away, and with three hundred enemies in Weiwerd itself, Major LaPrairie's company was in a difficult situation. The Germans in Weiwerd launched two strong counter-attacks in an attempt to recapture the bridge. Both counter-attacks were repulsed and thirty Germans were killed.

The Irish Regiment's B Company supported by tanks attacked Weiwerd. Over three hundred German troops, their only escape route denied them by Major LaPrairie's company, surrendered. The rest of the Irish Regiment crossed the bridge and within hours broke the German resistance, capturing over 1300 prisoners.

The capture of the intact bridge by the Company under Major LaPrairie allowed the passage of tanks, and they were responsible for the complete collapse of the eastern German defenses of Delfzijl and the capture of over 1600 prisoners. Major LaPrairie was awarded a Distinguished Service Order medal for his gallant action at Weiwerd in July 1945.