Canada said on Friday it was assessing the future of El Al flights to Toronto after one of the Israeli airline's planes was diverted twice because of an unspecified security threat.

Officials would not say what Thursday's threat had been but security experts speculated that it might have involved a shoulder-fired missile.

Transport Minister David Collenette said police and officials from his ministry were investigating the nature of the security threat to El Al flights headed for Toronto's Pearson Airport.

"As for subsequent El Al flights, that is something we will have to deliberate [on], considering the various intelligence we receive... I can't answer what is going to happen with other El Al flights," he told a news conference.

"This was a specific threat against El Al at Pearson Airport. I want to assure travelers that there is not a problem with traveling to Pearson, to Toronto."

The El Al jet was bound for Toronto from Tel Aviv and was forced to land first in Montreal, and then again in Hamilton, Ontario, to allow some passengers off. It then continued to Los Angeles.

The plane again landed at Hamilton instead of Toronto on its return leg on Friday, a spokesman for Hamilton's airport said.

A spokesman at the Israeli embassy in Ottawa said Israel was fully co-operating with the investigation.

(Reuters)