Chinese authorities have seized assets worth more than 90 billion yuan (£8.7 billion, $14bn) from the family and associates of former security chief Zhou Yongkang.

In one of the biggest corruption scandals in recent Chinese history, more than 300 of Zhou's relatives, staff, political allies and associates have been taken into custody by authorities or questioned in recent months, a source told Reuters.

Communist party anti-corruption officials and prosecutors froze bank accounts with deposits totalling 37bn yuan (£3.6bn) and seized domestic and overseas bonds with a combined value of 51bn yuan (£4.9bn) after raiding homes in Beijing, Shanghai and five provinces.

Investigators also confiscated some 300 apartments and villas, antiques, contemporary paintings and more than 60 vehicles, the sources added. Other items seized included expensive liquor, gold, silver and cash in local and foreign currencies.

The seized assets had a combined value of at least 90bn yuan, the sources said.

Those arrested include Zhou's former television host wife, his eldest son, and his brother.

Zhou is the most senior figure arrested in president Xi Jinping's anti-corruption purge.

The investigation into Zhou and his associates was ordered last year, but some see it as political payback for Zhou's support for disgraced party official Bo Xilai and his opposition to Xi.

"Zhou Yongkang is tough and claims it's political persecution," the source said.

Zhou rose through the party ranks to become one of the most feared members of the politburo, where as head of domestic security his budget exceeded the defence budget.

Previously, Zhou was involved in China's oil and gas sector, and several of his associates from this period have been placed under arrest.