GENEVA (AP) — Switzerland has blocked almost 1 billion Swiss francs ($1.03 billion) linked to rulers in four Arab Spring nations, a senior government official said Tuesday.

Since early 2011, the Swiss government has seized assets tied to rulers in Syria, Libya, Tunisia and Egypt, including including 700 million francs ($751 million) stashed away by former President Hosni Mubarak and his aides, said M. Valentin Zellweger, head of the Swiss foreign ministry’s international law department.