CAIRO — An opposition lawmaker who had called for democratic elections in Egypt to end decades of unopposed rule by President Hosni Mubarak was sent to jail Monday for 45 days.

The abrupt arrest of Ayman Nour on forgery charges comes amid a mounting debate over Mubarak´s seemingly open-ended run as president, along with fresh discontent sparked by speculation that the president hopes to pass the job to his son someday.

As head of the Al Ghad Party, which was established last fall, Nour has pushed for constitutional reform, freer political debate and an open election to replace the yes-no referendums that have repeatedly returned Mubarak to office unopposed.

The government accused Nour of faking all but 14 of the thousands of signatures he collected to form his party. The 45-year-old´s parliamentary immunity was lifted over the weekend, and security officers raided his home, seizing computers and files.

Nour´s wife and supporters dismissed the forgery charges as a pretext for arresting the outspoken lawmaker. On Monday, Nour told a judge that his arrest would "hinder the democratic process and reform in Egypt." He told an Egyptian rights group that he had been beaten during his arrest.

"This is not a legal case," his wife, Gamila Ismail, said. "Legally he´s done nothing wrong at all. This is a very dirty trick from the ruling regime."

In Washington, a State Department spokesman said the U.S. was concerned about the arrest.

"He is one of Egypt´s most prominent opposition leaders," Richard Boucher said. "The arrest, in our mind, raises questions about the outlook for a democratic process in Egypt."

The political mood in Egypt has been tense in recent months. Mubarak, 76, who has ruled since the assassination of Anwar Sadat in 1981, has hinted that he will stand for a fifth term in a referendum this year. Many Egyptian observers believe that Mubarak´s son Gamal is being groomed to eventually take over the presidency.

Both prospects cause unease among Egyptians, who have become more outspoken in recent months against Mubarak´s hold on power. Opposition figures have grown more insistent in their calls for constitutional reform. In a measure of the depth of discontent, protesters in December took the bold step of demonstrating in the streets against Mubarak´s possible reelection.

Nour had been among the more vocal critics. Ahead of reform talks being held this week between opposition parties and Mubarak´s National Democrats, he fired off a letter to the ruling party. He called for Mubarak to participate in the debate and for the discussions to be open to the public.

Nour also held a dinner last week for former U.S. Secretary of State Madeleine Albright, who was visiting Egypt to discuss political reform.

"People thought that he went too far," said Ismail, his wife. "The regime cannot tolerate a genuine party or a genuine popular movement."

Since being recognized in October, Al Ghad has gained thousands of members, its leaders say. It recently opened a new headquarters, and its newspaper is expected to begin publishing this month.

When government officials approved the party´s formation, "they felt they were making a compromise," Wael Nawara, an aide to Nour, told Reuters. "Then they were surprised at the following the party won, so then they wanted to teach a lesson to anyone who took a free and strong position." (Copyright 2005 Los Angeles Times 02/01/05)