The United States has protested to Israel the alleged torture of an Arab American who contends he was brutally mistreated during five weeks in an Israeli-supervised detention center after he was arrested in early February in south Lebanon.

The allegations of torture, including beatings, electrical shocks and burning with a cigarette, are contained in an affidavit filed with the U.S. Embassy in Tel Aviv by Ghazi Dabaja of Dearborn, Mich., a naturalized American of Lebanese Shiite origin.

The Israeli Embassy last night said Dabaja's allegations that an Israeli officer was involved in his torture were "totally baseless." Spokesman Yossi Gal said Dabaja had been arrested on suspicion of involvement in the planned assassination of four officers of the Israeli-supported South Lebanon Army (SLA). During Dabaja's interrogation, the Israeli army intervened to halt "improper treatment" by an SLA officer, Gal added.

According to confidential State Department cables provided to The Washington Post, Dabaja said he was picked up Feb. 12 by the SLA a day after arriving from the United States with his 8-year-old son in Bent Jbail, the home town of his parents which is three miles from the Israeli border.

Dabaja's allegations provoked the U.S. ambassador to Israel, Thomas R. Pickering, to take up the case with Israeli Defense Minister Yitzhak Rabin at a reception March 19.

Pickering told Rabin that it was "absolutely unacceptable" that an American be held for 30 days without informing the United States, according to the cables. He said Washington expected an apology and an Israeli commitment "not to repeat the process."

Pickering told Rabin, according to one of the cables, that "to the best of our knowledge and belief, he [Dabaja] had been mishandled either with the cooperation of the IDF [the Israeli Defense Forces] or at least in the presence of IDF personnel."

A State Department spokesman said yesterday that the United States had "made clear" to Israel its concern "over the circumstances under which Mr. Dabaja was detained. We made clear that such detention was unacceptable."

The spokesman refused to comment any further on the Dabaja case. But another U.S. official, who asked not to be identified, said that although a protest has been lodged with the Israeli government, there has been no response yet from Tel Aviv. Efforts to contact Dabaja, who reportedly has returned to Lebanon for another visit, were unsuccessful.

Dabaja's account of his arrest, detention and torture, contained in a sworn affidavit March 20 at the U.S. Embassy in Tel Aviv, was given two days after he was released by Israeli authorities to a U.S. official at the Israeli border town of Metulla.

According to his affidavit, Dabaja was picked up from his father's home and taken to a detention center in Khiam near Metulla, where he was questioned by what he first said were "three Israeli men." Later he told U.S. Embassy officials that the trio included two members of the SLA and one Israeli officer, whom he said was called "Yaaki."

Dabaja later told U.S. officials that his guards told him that Yaaki, who wore an IDF uniform without any insignia, was in charge of the camp.

Yaaki, according to Dabaja's testimony, was present at most of the torture sessions. Dabaja said his own head was covered by a black bag after the initial session but he was able to identify Yaaki by his voice.

Dabaja said he handed over his American passport the first day and told his interrogators that he had come to visit his parents and to purchase $25,000 worth of shoes and other items in Lebanon for later resale in the United States.

Israeli Embassy spokesman Gal yesterday said Dabaja had relatives in the Shiite Amal militia organization as well as in the extremist Hezbollah living in southern Lebanese villages. He was involved in a plot to kill four SLA security officers, Gal said, and had obtained explosives, and a Kalashnikov assault rifle with a silencer for that purpose.

Dabaja had been arrested by the same security officers who were targeted by the assassination plot, Gal said.

"Once Israeli security officers became aware of his situation, an order was given that an Israeli officer would be involved in the case so that the prisoner would not suffer improper treatment," Gal said.

Consequently, Dabaja was transferred to the Khiam detention center and "the improper treatment" by the SLA was halted because of the Israeli intervention, Gal said. The spokesman added that an SLA interrogator had used "methods unacceptable to Israel on the prisoner."

According to Dabaja's version, as contained in his affidavit:

"The second day one Israeli whose name is Yaaki started beating me on my face and all over my body. I was also subjected to electrical shocks on all parts of my body, including my penis and testicles.

"I was handcuffed with hands behind my back and hung from the ceiling naked, my feet and toes barely touching the ground. Cigarette burns were applied to my hands and stomach, water was poured over me and my body hair on my chest and arms were pulled by some people while Yaaki supervised.

"A hood was placed over my head. I was also beaten repeatedly across the back and legs with electrical cables. They twisted my breasts."

Dabaja said he lost consciousness "many times" and was taken twice to a hospital for treatment "because I was in much pain and unable to sleep." He said he was given Valium.

In one cable to Washington, the U.S. Embassy in Israel reported that members of its staff had "seen the handcuff marks and cigarette burns on his hands and wrists."

Dabaja said he kept asking to see his son but was told by his interrogators "something to the effect that he must have been the one we shot yesterday."

Dabaja told U.S. consular officials that he was subjected to daily beatings and torture during the first week to 10 days after his arrest. After the second time in the hospital, however, he was questioned intensively again for three days but was not tortured. Subsequently, he was generally left alone, according to the affidavit.

According to one cable, U.S. Embassy officials in Tel Aviv contacted the Israeli foreign ministry 11 times seeking information about Dabaja. Except for confirming the man's arrest, Israeli authorities refused to provide "other relevant details" or access, the cable said.

Rabin told Pickering he had no knowledge of the Dabaja case and would be "chagrined" if the allegations of Israeli torture proved true after he investigated them, according to one cable. Rabin also said he would take steps to see that such mistreatment of Lebanese detainees did not happen again.

On March 17, more than one month after his detention, Dabaja said he was visited by his father and brother and given new clothes to wear, according to the affidavit. The next day he was taken by the Israeli army to Metulla and released.

In one cable from Pickering to the State Department, the U.S. ambassador also asked the Israeli defense minister to take "all necessary steps" to allow the Geneva-based International Red Cross to have access to the Israeli-supervised detention center in Khiam, located in the strip of Lebanese territory run by the SLA.

Rabin told Pickering, according to the cable, that he would give "full consideration to the possibility of opening up the al Khiam facility."

Dabaja estimated that over 300 people, apparently all Lebanese Shiites, were being held at the Khiam center.