The Germans then offered terms under which they would surrender but they were rejected by Botha and the war continued. On 12 May Botha declared martial law and having cut the colony in half, divided his forces into four contingents under Coen Brits, Lukin, Manie Botha and Myburgh. Brits went north to Otjiwarongo, Outjo and Etosha Pan which cut off German forces in the interior from the coastal regions of Kunene and Kaokoveld. The other three columns fanned out into the north-east. Lukin went along the railway line running from Swakopmund to Tsumeb. The other two columns advanced on Lukin's right flank, Myburgh to Otavi junction and Manie Botha to Tsumeb and the line's terminus. The men who commanded these columns, having gained their military experience fighting in Boer commandos, moved very rapidly. The German forces in the north-west made a stand at Otavi on 1 July but were beaten and surrendered at Khorab on 9 July 1915.