STOCKHOLM, March 18 (Reuters) - Russia, China and Iran are the biggest threats to Sweden, the Swedish Security Service (SAPO) said on Wednesday in its annual report on threats facing the country.

The security police has warned in recent years of rising threats, above all from a Russian state increasingly prone to risky ventures in support of its war in Ukraine, including through destabilising hybrid attacks around Europe.

Iran has also long been labelled a serious threat and authorities have noted how criminal networks in Sweden, which has spent the past decade dealing with a wave of gang-related crime, have been used by state actors to carry out violent acts.

"The U.S.-Israeli military operation against Iran, and the countermeasures carried out by Iran, have increased the threat against American, Israeli and Jewish targets in Sweden," Security Service Chief Charlotte von Essen said in the report.

(Reporting by Niklas Pollard and Johan Ahlander, editing by Terje Solsvik)