Conflicting reports from government officials and several unofficial sources have left unclear the death toll in a clash here last Thursday between university students and riot police that apparently was the worst such violence in Jordan in a decade.

Several students, unofficial university sources and medical personnel said earlier this week that at least six persons were killed when a special police force from Amman stormed the campus of Yarmouk University after two months of sporadic unrest.

But yesterday, Dr. Abdul Hafiz Momani, director of the government-run Princess Basma Hospital, repeated the Interior Ministry's original statement that only three students were killed. All appeared to have died of asphyxia -- which can be caused by strangulation or suffocation -- and one of them also suffered a broken nose and a crushed foot, Momani said.

A physician who said he has treated 11 students privately because they feared arrest if they went to hospitals said he knew of six students who had been killed. "Some university faculty saw [riot police] hitting students after they had fallen to the ground and kicking them," he said.

Such protests and the harsh crackdown are rare in Jordan, and the political implications are not clear. There is a consensus in western diplomatic circles that the students' demands were related mainly to internal university matters.

Other observers, however, said the fundamentalist Moslem Brotherhood had a role in inflaming students against the university's administration because of a feud with its president and as a way of indirectly showing displeasure with a move by King Hussein last November to rein in politicized Moslem fundamentalism as Syrian-Jordanian rapprochement was getting under way.

Several Jordanian and western observers said they thought authorities had overreacted at Yarmouk because they feared that outside political forces, particularly those linked to the underground Jordanian Communist Party, would try to exploit the student unrest.

At least 17 members of the Communist Party and the Marxist Popular Front for the Liberation of Palestine were arrested last weekend, according to Information Minister Mohammed Khatib, after they reportedly organized a small protest against the "Yarmouk massacre."

Sources said as many as 800 students were taken into custody by police in the raid on the campus last week, but authorities gave no figures. On Hussein's orders, however, all those detained were released Sunday. A special Cabinet committee is investigating the incidents.

The trouble at Yarmouk, which has 14,000 students, began in March when engineering students protested against new fees. There were further demonstrations, reportedly small and peaceful, to mark a Palestinian protest day in the Israeli-occupied territories and to protest the U.S. raid on Libya.

Five students named as organizers of the protests were expelled and, as their situation was being negotiated, a "warning strike" was called, followed by growing protests that, by May 13, spread into the city, where some students stoned police, according to witnesses.

Early on May 15, as about 2,000 students sat in the university square, about 75 members of the central security police from Amman stormed through the gates, witnesses said, clubbing the students and taking them to detention centers.