Turkish air strikes have killed at least 14 fighters deployed by the Syrian regime in support of Kurds battling Turkish-led rebels in the northwestern enclave of Afrin, the Britain-based Syrian Observatory for Human Rights said Friday. Three Kurdish fighters were also killed in the strikes late Thursday on the village of Jamma in the enclave on the Turkish border, it said. Turkey-led Syrian rebels have advanced steadily since launching an assault on January 20 on Afrin, which is controlled by the Kurdish Peoples Protection Units (YPG). The Syrian regime deployed fighters to the enclave a month later after the Kurds called for help. YPG spokesman in Afrin, Birusk Hasakeh, said Turkish warplanes targeted the positions of fighters linked to the Syrian army in Jamma, causing casualties, but did not provide a precise toll. Pro-regime fighters are present on several fronts in the enclave, according to the Kurds. Turkeys military declined to comment on the Observatory report, but the Turkish state-run Anadolu news agency reported on Friday that Turkish attack helicopters had killed nine YPG fighters in the west of Afrin. Turkey also suffered heavy losses in Afrin on Thursday. The military said eight soldiers were killed and 13 wounded. The days toll brought the number of Turkish soldiers killed since the start of the operation to at least 40. The Observatory says more than 140 civilians have been killed in Turkish bombardment, but Turkey denies the claim and says it takes the "utmost care" to avoid civilian casualties.