Based on the rank, I believe this is probably your man. He was a Lieutenant in the OVS Police.
Jacques Malan (1990), p. 205
Lt. S.J. LIEBENBERG
Sarel Johannes Liebenberg is op 17 Februarie 1874 in Philippolis gebore en op 24 Februarie 1945 op Vryheid oorlede.
Hy was lid van die Vrystaatse polisie alwaar hy tot luitenant vorder.
In die Tweede Vryheidsoorlog het hy eers onder genl. M. Prinsloo en daarna onder genl. C.R. de Wet geveg.
Na die oorlog het hy eers in die Vrystaat en daarna in Suidoos-Transvaal geboer. In 1920 is hy na Vryheid, waar hy tot sy dood gebly het.
Sarel Johannes Liebenberg was born on 17 February 1874 in Philippolis and died on 24 February 1945 in Vryheid.
He was a member of the Free State police where he attained the rank of lieutenant.
In the Second War of Independence he first served under General M. Prinsloo and then under General C. R. de Wet.
After the war he first farmed in the Free State and then in the South-Eastern Transvaal. In 1920 he moved to Vryheid, where he remained until his death.
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