Nearly 12 million Egyptians went to the polls today to confirm President-designate Hosni Mubarak as the successor to slain president Anwar Sadat.

While the transition of power was validated, diplomatic sources said that Egyptian authorities have dismissed at least 200 suspected Islamic extremists from the armed forces and arrested hundreds of others outside the Army.

Reminders of continuing internal and external political tension surfaced in an hour-long battle this morning near the pyramids between police and what was described as a band of five extremists, and at Cairo's international airport, where two bombs exploded as suitcases were unloaded from a plane just arrived from Libya.

One airport worker and three security men were wounded in the bombing, the Interior Ministry said. The religious fundamentalists involved in the internal fighting were reported captured.

Interviews with a dozen voters at Cairo polls today indicated that a desire for security, continuity and stability helped bring out voters for Mubarak. Sadat's assassination has deeply shaken this nation of 42 million people, and the voters clearly feared Egypt's new violence and sudden uncertainty.

Security was obviously a priority of police today. Voters were carefully searched for arms, and there were identity checks in front of polling areas. Riot police were stationed throughout the city.

The results of the elections are expected to be made public early Thursday, and Mubarak is scheduled to be sworn in as Egypt's new president at noon. The only voting result of real significance will be the rate of abstention, which ran about 8 percent in last month's referendum on Sadat's crackdown on sectarian extremists and opposition elements.

Word of the current wave of arrests and dismissals of military officers and soldiers, which appear to mark the onset of a full-scale campaign to weed out suspect power factions and track down Moslem fanatics, came despite official claims that only 18 officers had been cashiered and transferred to civilian jobs.

Despite professions of confidence in the armed forces by Mubarak and other top officials, the government seems to be taking no chances and is going carefully through the ranks of the Army in search of anyone with militant Islamic views.

In addition, as the government continues its investigation of what appears to have been the massive security breach that allowed Sadat's assassins, two of them civilians, to slip into the military parade he was reviewing when he was shot, at least eight security officials have been called in for questioning.

A similar manhunt for extremists outside the armed forces is reportedly also under way. While officials have said nothing and Western diplomatic sources give no precise numbers, leftist opposition leader Khalid Mohiebdin told reporters that 1,000 Moslem extremists had already been picked up since the assassination.

Mohiebdin, who leads the small Unionist Progressive Party, proved to be fairly accurate in his claims during the September crackdown on religious extremists and opposition elements, which involved the arrests of more than 1,500 people.

Today's shootout, the first major street skirmish between security authorities and Moslem extremists in Cairo since the assassination of Sadat, took place along the main road leading to the pyramids. It involved two men police were seeking in connection with last Thursday's uprising in the southern town of Asyut, during which 44 policemen and nine Moslem fundamentalists were killed and more than 100 others wounded.

The two men, Tarik and Abud Zoumar, had apparently taken refuge here in Cairo with three other extremists. Other reports said the other three may also have been involved in the Asyut insurrection.

Egyptian television this afternoon showed the badly pockmarked house where the fighting had taken place, and said the police had confiscated one submachine gun, one automatic rifle, four handguns and quantities of explosives and ammunition.

During today's balloting, Sadat's widow, Jehan, predicted to reporters as she voted at the official residence in Giza that "everyone in our country will say yes for our new President Mubarak. He is our hope now. We must be all together for the future of Egypt. This is what my husband wanted."

At three polling stations visited by this reporter in different suburbs of Cairo, Egyptians seemed to be turning out in exceptionally large numbers to vote for Mubarak.

"He is the same as the other," said one grizzled old voter, referring to Mubarak as the new Sadat, as he left the voting booth in the Khedive Ismail secondary school in the downtown area.

Signs outside the makeshift polling stations, mostly in schools, showed pictures of the 53-year-old Mubarak captioned with slogans: "Yes, for the peace process, democracy and welfare," and "Yes, for national unity and security."

The small square ballot itself said simply, "Do you agree with the election of Mohamed Hosni Mubarak as president of the Arab Republic of Egypt?" Below were two circles, a white one for "agree" and a black one for "other than agree."

In the past, the results of Egyptian referendums -- the percentage of turnout as well as that of approval -- have not been taken very seriously because both figures have almost always run close to 100 percent.

But visits to voting booths today that were also sampled in the last referendum indicated that there was in fact a large turnout. Reporters visiting a number of villages in the Nile Delta said the same was true there.

One veteran polling officer at a station in the predominantly Christian quarter of Shubra al-Khaymah said it was the largest turnout he had witnessed in 16 years. "People are worried about the unrest in the country and they want order," he commented.

The second incident of violence marring today's referendum occurred at the main Cairo airport when two parcel bombs went off on the tarmac among a stack of suitcases waiting to be inspected before they were brought into the terminal.

The suitcases were aboard an Air Malta plane filled with Egyptian workers that had come via Malta from Libya. Security sources said that only a delay in the landing and security check procedures prevented the bomb from going off inside the main terminal building.

Libyan leader Muammar Qaddafi, who opposed Egypt's peace treaty with Israel, was a bitter enemy of Sadat and he openly rejoiced at his death.

But Libya tonight denied that the bombs originated in Tripoli and said "revolutionary" Egyptians were responsible.

Libyan radio has encouraged Egyptians to rise up and overthrow the entire regime since Sadat's assassination and Mubarak's pledges of a continuity in Egypt's foreign policy.