JERUSALEM (AP) _ Police seized more than a million Ecstasy pills seized and arrested 49 people in the Netherlands, Israel and other countries in a sweep carried out by hundreds of officers, Israeli authorities said Tuesday.

The police estimate that the drug ring manufactured and distributed tens of tons of narcotics, supplying the drugs to Western Europe, Israel and the United States.

There were 25 arrests in Holland, eight in Israel and the remaining 16 in other countries that were not identified.

The sweep involved 400 Dutch police and an undisclosed number of Israelis, authorities said.

An Israeli undercover agent, whose name was not disclosed, wore a false beard and a wig to conceal his identity Tuesday as he told reporters how he spent ten months undercover in Holland to crack a the Dutch-Israeli drug ring.

The agent was recruited for the operation from the ranks of the police elite anti-terrorist unit. He is expected to give evidence at the trials in Holland, in disguise and with his voice electronically distorted.

The joint Israeli and Dutch police operation, code-named ``Octopus,'' probed as its main targets two Israelis and a Dutchman, all of them now under arrest. The alleged head of the ring was an Israeli, Eddy (Edmond) Sason, who moved to Holland 20 years ago and is married to a Dutch woman, said Col. Dudi Cohen, deputy chief of police intelligence.

Sason is to be prosecuted in Holland, but the Israeli police said they may request the extradition of some of his accomplices.

``I'm very sorry to say that Israelis play a considerable role in the international drug trade,'' Cohen said.

Arms, explosives and cash also were seized, authorities said. Three Ecstasy laboratories and a large marijuana field were uncovered.

A study last year concluded that people who use Ecstasy, a combination of a hallucinogen and a stimulant, are putting themselves at risk of developing brain damage.