King Indra seems to continue the builder tradition of his predecessor. He continued the construction of Manjusrigrha temple (Sewu complex), and according to the Karangtengah inscription (dated 824) responsible for the construction of Venuvana temple, connected to Mendut or probably Ngawen temple. He was also probably responsible for the conception and initiation of the construction of Borobudur and Pawon temple. Dharanindra ascends as the Maharaja of Srivijaya. The nature of Shailendras' close relations with the neighbouring Srivijayan empire based on Sumatra is quite uncertain and complicated. It seems that in earlier times, Shailendra family belonged within Srivijayan mandala sphere of influence. And for a later period of time, Shailendras' monarch rose to become the head of Srivijayan mandala. The shift that rendered Shailendras in return to become the ruler of Srivijaya was unclear. Was it led by military campaign by Dharanindra against Srivijaya in Sumatra, or more likely formed by close alliance and kinship between the house of Shailendra and the Maharaja of Srivijaya. Based on the Ligor inscription, Laguna copperplate inscription and Pucangan inscription, the influence and knowledge of the Mataram Kingdom reached as far as Bali, southern Thailand, the kingdoms in the Philippine islands, and the Khmer in Cambodia. In 851 an Arabic merchant named Sulaimaan recorded an event about Javanese Sailendras staging a surprise attack on the Khmers by approaching the capital from the river, after a sea crossing from Java. The young Khmer king was later punished by the Maharaja, and subsequently, the kingdom became a vassal of the Sailendra dynasty. In 916 CE, a Javanese kingdom invaded the Khmer Empire, using 1000 "medium-sized" vessels, which resulted in a Javanese victory. The head of the Khmer king was then brought to Java. The pacifist ruler Dharanindra's successor was Samaragrawira (r. 800–819), mentioned in Nalanda inscription (dated 860) as the father of Balaputradewa, and the son of Śailendravamsatilaka (the ornament of Śailendra family) with stylised name Śrīviravairimathana (the slayer of enemy hero), which refer to Dharanindra. Unlike his predecessor the expansive warlike Dharanindra, Samaragrawira seems to be a pacifist, enjoying a peaceful prosperity of interior Java in Kedu Plain, and more interested on completing the Borobudur project. He appointed the Khmer prince Jayavarman as the governor of Indrapura in the Mekong delta under Shailendran rule. This decision was proven as a mistake, as Jayavarman later revolted, moved his capital further inland north from Tonle Sap to Mahendraparvata,