Former Solidarity leader Lech Walesa was hospitalized in his native Gdansk, northern Poland with a high fever and stomach problems and was undergoing tests, officials said Thursday.
Walesa had checked into the hospital Wednesday afternoon and was to stay several days in the gastric ward, DPA reported.
The 67-year-old had been travelling often by plane recently, and that could have made him sick, his friend Jerzy Borowczak told broadcaster TVN 24. In the past two weeks, Walesa has visited the United States, Kuwait, Italy, Latvia and Estonia.
Photos that Walesa posted on his blog show him standing with hospital staff and lying in a hospital bed.
The Nobel Peace Prize recipient suffers from heart problems and had a pacemaker put in three years ago.
Walesa led protests in the shipyards of Gdansk in the late 1970s that helped topple Poland's Communist regime a decade later.
He was the country's first elected president after Communism collapsed, and served in that office from 1990 to 1995.