A Hong Kong Red Cross worker shot in Indonesia will live with bullet fragments lodged in her neck for the rest of her life, says the surgeon who operated on her. Gunmen riddled the white Red Cross-marked four-wheel-drive vehicle with bullets 3.5km north of Lam No on the west coast of tsunami-ravaged Aceh province on Wednesday night, hitting Eva Yeung Yee-wa in the neck. Tan Chong Tien, who operated on Ms Yeung, 28, at Mount Elizabeth Hospital in Singapore on Thursday night, said he had removed a large bullet fragment from the right side of her neck. Five fragments on the other side of her neck were too minute to remove, he said. Investigators found 17 spent bullet casings on the roadside where the attack took place. Red Cross spokesman Virgil Grandfield said five bullets had hit the vehicle. 'At least six to eight armed men perpetrated the attack. According to Eva, they jumped up from the ditches at either side of the road. The men shot at close range. Considering the circumstance, the darkness especially, it would have been very difficult, if not impossible, for someone to know they were firing on a Red Cross vehicle ... It was pitch black.' Mr Grandfield said the International Federation of Red Cross and Red Crescent Societies was considering whether to strengthen rules which require aid workers not to travel after dark and to notify local authorities of their movements. The rough terrain along the highway from the provincial capital Banda Aceh to Lamno highway, where much of the road was washed away in the tsunami, may explain why Ms Yeung and her Indonesian driver were on the road after dark, he said. Dr Tan, who led a team of three doctors in the 90-minute surgery at Mount Elizabeth Hospital, said: 'She is very fortunate that the bullet fragments only went as far as the deep muscle near the spine.' Ms Yeung remained in intensive care last night and is likely to be discharged in a few days. She will remain in Singapore for a week for follow-up checks, the doctor said. Her father Yeung Chun-tak and aunt flew to Singapore to join her mother Fung Kwai-fong, brother and boyfriend who arrived in the city on Thursday. Speaking at the hospital yesterday, her family said she was sitting up and in good spirits. Her mother described her as a 'very cheerful and brave girl' who had always wanted to help others. Ms Yeung is part of a relief team administering aid to 130,000 families along the coast of Aceh. She was on a six-month secondment and arrived in Aceh in mid-February. Last year she took part in flood relief and prevention programmes on the mainland.