China's central bank, the Housing Ministry and top financial and securities regulators summoned financial chiefs of six leading property developers Tuesday for briefings on the companies' liquidity and debt situations, Caixin learned from sources. The developers are state-owned China Resources Land, China Overseas Land and Investment, Poly Real Estate Group, mixed-ownership developer China Vanke, Gemdale and private developer Longfor Properties. The six are the few big developers that have avoided defaulting amid the widespread liquidity crisis in the real estate sector.