JERUSALEM -- In the evolving duel between Palestinian attackers and Israel's security forces, the small, secretive and resilient Islamic Jihad movement now says it favors car bombs that are far more powerful than the small explosive charges strapped to suicide bombers.

The tactic is a response to the tough security measures Israel has taken against suicide bombers who strike on foot, and it has the potential to greatly increase Israeli casualties.

For the second time in four months, Islamic Jihad attackers maneuvered an explosives-laden car up to a bus and unleashed a massive fireball. In Monday's attack, 14 people were killed near the northern town of Hadera. In an almost identical bombing on June 5, 17 people were killed near Megiddo, 15 miles to the northeast.

In the same area, police foiled an attempted bombing Sept. 5 after tracking down a car loaded with 1,300 pounds of explosives, one of the largest bombs ever uncovered in Israel.

Islamic Jihad has carried out dozens of attacks in the past two years. But its bombers have often made mistakes -- blowing themselves up prematurely, getting caught before reaching a target or detonating bombs in uncrowded areas.

The car bombs have the potential to send the Israeli death toll skyrocketing.

"They could be looking to concentrate their energies on fewer attacks, but want to show they can cause a larger number of casualties," said Boaz Ganor, head of Israel's International Policy Institute of Counter-Terrorism.

The suicide bombers' explosives are limited to what they can conceal on their bodies. The car in Monday's bombing carried more than 200 pounds of explosives.

Over the past two years, 79 suicide bombings have killed 292 people.