ZURICH - Swiss authorities said on Thursday they had arrested seven people of North African origin suspected of plotting to attack an Israeli El Al airliner.
The Swiss attorney general's office said the attack was to have been carried out in Switzerland but it did not specify how, when, or precisely where. It said no explosives had been found.
"We do not have an exact date. We just know about the plans. We got wind of them towards the end of last year," Jeanne Balmer, a spokeswoman for the attorney general's office, told Reuters. "I cannot go into detail. The investigation is not over."
The suspects had been in contact with other groups in France and Spain, which have also been uncovered by the police, a statement from the attorney general added.
"The inquiry has...made it possible to show that this cell had very seriously envisaged committing an attack in our country on an airliner belonging to the El Al airline," it said.
El Al operates scheduled flights between Tel Aviv and the Swiss cities of Zurich and Geneva.
Israel's Yedioth Ahronoth newspaper reported last month that Swiss and French intelligence agents had foiled a plot to shoot down an El Al plane over Geneva in December using a rocket-propelled grenade.
A senior Israeli security official declined comment on the arrests in Switzerland but said: "Past experience and intelligence received from time to time underscore efforts by terror groups to attack Israeli targets abroad." One of the Swiss suspects was in touch with an Algerian, known as Mohamed Achraf, who was extradited to Spain last year.
The Swiss news website Swiss Info said Achraf was arrested in Switzerland and was the suspected mastermind of a plot to attack a court building in Madrid.
A first round of seven arrests was made near Zurich and Basel on May 12 and four of them were later released, said Balmer. More arrests followed in other parts of Switzerland.
Police suspicions were first aroused after a series of robberies committed early last year by what the attorney general's office described as a highly organised group of about a dozen.
An investigation concluded that part of the booty "was transferred for the benefit of a terrorist organisation", the statement said.
In France, the Paris prosecutor's office said six people suspected of belonging to a funding network for an al Qaeda-linked Islamic group had been arrested on Tuesday in an operation linked to the Swiss arrests.
A seventh person was arrested on the same day in Switzerland, it said.
The Paris prosecutor's office said the group had committed robberies in Switzerland and Spain and transferred funds to the Salafist Group for Preaching and Combat (GSPC), an al Qaeda-linked group on the US list of terrorist bodies.
"Justice authorities in both countries have for the first time uncovered the financing of extremist Islamic terrorist activity through violations of common law," the office said in a statement.
It made no reference to any plans to attack an El Al plane.