CAIRO, JUNE 4 -- Egyptian and U.S. security officials have expressed increasing alarm in the wake of three shooting attacks here on American and Egyptian officials in the past month by terrorists using automatic weapons and striking brazenly in the heart of this crowded capital.

Targets of the attacks have been a former Egyptian interior minister, a prominent magazine editor and three U.S. Embassy staff members, including the chief of embassy security, whose car was hit by gunfire last week in what U.S. security experts sent from Washington have called a "very professional" and "well-planned" attack.

The attacks caught Egyptian security forces by surprise. "That's the worry," said one western official. Still, U.S. and western officials say they see no indication that the new violence is part of any general political discontent here and they are heartened that so far, Egypt's leadership under President Hosni Mubarak has not called for harsher police measures that would retard the country's gradual movement toward a more open democracy.

The latest target was the chief editor of the government-controlled Mussawar magazine, Makram Mohammed Ahmed, who was fired upon from a car that pulled alongside his as he drove through the city center late yesterday.

The burst of bullets that peppered Ahmed's car caused only minor injuries to him and several passers-by. Police have made no arrest.

Ahmed is well known for his outspoken editorial attacks on Moslem fundamentalism and this week had written a stinging cover story on the terrorist attacks that preceded the attempt on his life.

Only one of the targets in the three attacks -- former interior minister Hassan Abu Basha, 65 -- was seriously wounded. His hip was shattered by a rifle bullet fired by one of three assailants on May 5.

It was the attack on Abu Basha that prompted Ahmed to write against Egypt's Moslem extremists, calling them liars and opportunists bent on taking advantage of Egypt's growing democratization to seize power through violence.

A little-known group that calls itself Egypt's Revolution took responsibility for last week's attack on the U.S. Embassy officials. The same group had said it carried out the March 1986 shooting of four Israeli Embassy officials that left one dead and three wounded. It also had claimed responsibility for the fatal shooting of an Israeli Embassy official in August 1985 in suburban Cairo and the wounding of an Israeli in 1984.

Egypt's Revolution, which is thought to be inspired by radical Palestinian groups, said in a statement last weekend that it "froze its activities for a certain period in order to give President Mubarak an opportunity" to change his political course away from American influence and Egypt's commitment to its Camp David peace accords with Israel.

It claimed it is preparing a "popular revolution" within Egypt's armed forces, warned the government not to hold planned joint military exercises with the United States in August and called for "free and honest elections under the supervision of the United Nations."

According to several security sources, the attack on Abu Basha and the magazine editor appear to have been carried out by Egyptian Islamic extremists, who were blamed for the assassination in 1981 of president Anwar Sadat and the rampage of violence that followed in Upper Egypt, where 90 local policemen were killed.

Although police conscripts rioted in the tourist area adjoining the pyramids here in February 1986, there have been no attacks on incumbent Egyptian political leaders since Sadat was slain. Last December, however, Egypt's top prosecutor announced that police had broken up a ring of 33 Moslem extremists, four of them Army officers, plotting to overthrow the government.

While there have been occasional threats, there had been no previous attacks on the estimated 15,000 Americans who live here, according to security officials.

U.S. officials have tightened some security measures to protect American officials and dependents, who already live under significant security as a result of embassy bombings and attacks in other Arab capitals in recent years. One sign of the times this week was the arrival of a new, heavily armored Mercedes for U.S. Ambassador Frank G. Wisner.

The immediate reaction by Egyptian and American officials to the surprise of three attacks in one month has been to question the effectiveness of Egypt's security forces, who are under the control of Interior Minister Zaki Badr.

In recent years, U.S. diplomats have been reporting to Washington the Egyptian leadership's contention that the brand of Islamic fundamentalism that swept over Iran in the late 1970s does not exist in all but a minuscule portion of the populace. Thus, Egyptian security forces have been able to keep radical elements under close surveillance and tight control.

After the first of the recent shootings, in early May, security forces arrested "several thousand" fundamentalists, according to a western official, and some western estimates put the total detained as high as 6,000.

The Abu Basha assailants left their fingerprints on soda bottles, and authorities arrested one suspect last month. This week, the Interior Ministry announced that it would soon bring charges against three fundamentalists allegedly tied to the attack.

One of those identified through fingerprints was among the hundreds of Moslem fundamentalists jailed in the wake of the Sadat assassination, according to one western official.