Saima Wani breathed her last yesterday at the SKIMS hospital here after battling for life for 17 days, he said.
The official said Saima was the sister of militant Sameer Ahmad Wani, who was killed in an encounter with the security forces, along with another militant, on January 24.
A 17-year-old boy, Shakir Ahmad, was killed and two women, including Saima, were injured during the clashes between protesters and the security forces near the encounter site.