But in 2002, both the Czech president, Vaclav Havel, and the C.I.A. concluded that there was no evidence to confirm the report. Mr. Atta did visit Prague on at least one occasion in 2000 and was denied entry when he arrived at a Prague airport later that year. But the report that he had met in Prague with an Iraqi intelligence officer, Ahmad Khalil Ibrahim Samir al-Ani, was based on unconfirmed statements of a single informant.

The erroneous report, attributed to miscommunication between the Interior Ministry and the intelligence services, may have tarnished Mr. Gross’s reputation abroad, but at home he remained popular, singled out by Mr. Havel as one of the nation’s up-and-coming young leaders. He was appointed prime minister in 2004. But his fall was even more rapid than his ascent. Just nine months later he was forced to resign over a scandal concerning the financing of his luxury apartment in Prague.

Stanislav Gross was born in Prague on Oct. 30, 1969. A railroad engineer by trade, he joined the leftist Social Democratic party in 1989, just weeks after the collapse of the Communist regime in Czechoslovakia. He soon began his rapid rise in party ranks, lauded as a natural political talent with great negotiating skills.

In 1992, he was elected to Parliament, and three years later he became the head of his party’s caucus in the lower house. In a 1998 snap general election, Mr. Gross, 29, was re-elected to Parliament with the third-highest number of preferential votes of all candidates nationwide.

Following the party’s poor showing at a European election in 2004, Mr. Gross moved to oust the Social Democratic prime minister, Vladimir Spidla, and took over the post.