WARSAW, Poland – Jan Nowak-Jezioranski, a wartime courier for the Polish anti-Nazi resistance and the director of Radio Free Europe’s Polish service during the Cold War, has died, Polish officials said Friday. He was 91.

Nowak-Jezioranski died Thursday in a Warsaw hospital. The cause of death was not immediately given.

“A great Pole, a hero and a great authority has gone,” Tadeusz Mazowiecki, Poland’s first democratic prime minister after communism’s end, said on state radio.

Nowak-Jezioranski fought in the brief 1939 campaign after Nazi Germany’s invasion of Poland.

After Poland’s defeat and occupation, he joined the resistance movement and fought in the 1944 Warsaw uprising against the Nazis.

He risked his life as a courier between the Polish government-in-exile in London and the Polish underground resistance in German-occupied Poland, completing five trips – including risky parachute jumps.

The uprising began Aug. 1, 1944, and lasted 63 days, leaving about 200,000 insurgents and civilians dead. Nowak-Jezioranski sneaked back out of Nazi-occupied Poland after the uprising failed, carrying intelligence material and film showing the struggle.

In Washington, the White House said President Bush mourned the passing of “a great Polish freedom fighter and American patriot.”

“Jan Nowak-Jezioranski pursued his values tenaciously, and contributed greatly to the building of a Europe whole, free, and at peace,” the statement said.

In London, Prime Minister Tony Blair’s office praised Nowak-Jezioranski’s courage.

There was no immediate word about funeral arrangements or survivors.