A few years later, they annexed Khiva Khanate in 1873. Because Turkmen tribes, most notably the Yomud, were in the military service of the Khivan khan, Russian forces invaded Khorazm, destroying many settlements and killing hundreds of Turkmens. In 1881, the Russians under General Mikhail Skobelev besieged and captured Geok Tepe, one of the last Turkmen strongholds. Geok Tepe is located close to Ashgabat. After the Turkmen defeat, the annexation of the present-day Turkmenistan was met with only weak resistance. Later in the same year, the Russians signed an agreement with the Persians. This agreement established the pernament Russian-Persian border, which became the present-day border between Turkmenistan and Iran. In 1897 a border agreement was signed between the Russians and Afghans.