Israeli police on Sunday went on high alert and beefed up their presence in the north following the discovery of a car loaded with explosives in Haifa.

Checkpoints were erected along the roads in the region, and security personnel enhanced inspections of passing vehicles, reported Israeli daily Ha'aretz.

The measures were staged after police sappers on Saturday night found and neutralized dozens of kilograms of explosives in a car parked outside a shopping center in the northern city of Haifa.

"This was a terror attack for all intents and purposes and its perpetrators came from the West Bank," Prime Minister Ehud Olmert was quoted as saying at Sunday's cabinet meeting, adding that "the security forces are already operating on the matter."

No detail has so far been released regarding the ongoing police investigation, expect that preliminary findings showed that the car belonged to a resident of Jerusalem.

A group dubbing itself the Galilee Freedom Fighters claimed responsibility for the thwarted attack, yet its credibility was questioned.