A jewellery workshop employee died yesterday evening just hours after police arrested six mainland men suspected of carrying out the violent robbery on Thursday that led to his fatal injuries. The 52-year-old man, surnamed Li, was injured when robbed of HK$400,000 worth of gold ornaments outside the Hung Hom KCR station at lunchtime on Thursday. He was attacked by four men as he was wheeling a trolley containing four cartons of ornaments out of the station at about 1.30pm. Li had just picked up the ornaments, which were being returned from processing on the mainland, from a courier inside the station. The robbers, one said to be armed with a knife, held him tightly by the neck and attacked him, causing severe head and facial injuries. They then escaped in a van, which was later found by police with a car believed to have been used in other robberies. Both were confirmed as stolen vehicles. Yesterday afternoon police raided a flat on Shun Ning Road, Cheung Sha Wan, and arrested six male illegal immigrants, aged between 21 and 37, suspected to be connected with the case. During the raid, one of the suspects, surnamed Lau, 24, jumped from the flat in a bid to escape, injuring himself. He was admitted to Caritas Medical Centre. His condition was not known. The others were being held overnight by the Kowloon West regional crime unit, police said. Police said they found four beef knives in the alley behind the building but none of the stolen ornaments had been recovered. Queen Elizabeth Hospital said the robbery victim died shortly before 8.30pm yesterday. A post-mortem will be conducted. Sources said it was suspected the arrested men could be connected with at least two robberies of similar style in Tsim Sha Tsui and Jordan Road last year. Thursday's heist was the third such robbery in five months. In July, two salesmen were chopped and robbed of HK$2.7 million worth of jewellery by three men at Tsim Sha Tsui. On June 23, a merchant and his sister were injured and robbed of HK$1 million worth of gold ornaments and jewellery in Yau Ma Tei.