The 27-year-old shot Ms Steenkamp through his toilet door.

He maintains he mistook her for an intruder.

“No words can adequately capture my feelings about the devastating accident that has caused such heartache for everyone who truly loved — and continues to love Reeva,” Pistorius wrote.

“The pain and sadness — especially for Reeva’s parents, family and friends consumes me with sorrow.

“The loss of Reeva and the complete trauma of that day, I will carry with me for the rest of my life,” he said.

The message was signed “Oscar“.

Pistorius is due to stand trial for premeditated murder on March 3 and more than 100 witnesses are due to attend including his ex-girlfriends Melissa Rom and Samantha Taylor and his sister Aimee.

Ms Steenkamp was shot in the head, elbow and hip through the locked bathroom door of Pistorius’s upmarket Pretoria home.

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