Meanwhile, Hulu Klang enjoyed unprecedented growth due to tin mining. Between 1849 and 1850, Raja Abdullah bin Raja Jaafar, Raja Jumaat's cousin, was appointed by the sultan as Klang's administrator. As Lukut's economic importance was slowly declining, that of Hulu Klang was rising. This attracted many labourers to relocate there, especially Chinese immigrants who had worked in Lukut. One person responsible for persuading the Chinese to move from Lukut to Hulu Klang was Sutan Puasa from Ampang. He supplied the mining colonies in Hulu Klang with goods ranging from rice to opium. As Hulu Klang prospered, several settlements started to rise up by the late 1860s. Two of them were Kuala Lumpur and Klang. A Chinese kapitan named Yap Ah Loy was instrumental in developing Kuala Lumpur.