Israeli police were on a heightened state of alert on Tuesday, a day after Palestinian militants carried out the first suicide attack in the Jewish state in a year.
"Our forces have been placed on a heightened state of alert as we fear a wave of terrorist attacks after Monday's attack in Dimona," Bertie Ohayon, a senior police officer, told public radio.
"We have mobilised thousands of police personnel and border guards, backed up by volunteers, to comb through densely-populated areas and carry out surveillance in sensitive areas, notably along the border with Egypt."
An Israeli woman was killed in the suicide attack carried out by two bombers in the desert town of Dimona, the first such attack on Israeli soil since January 2007.
The attack was claimed by the Al-Aqsa Martyrs Brigades, a group loosely linked with Palestinian president Mahmud Abbas's Fatah party, along with two other groups, who said the bombers were from Gaza.
The bombing came after a nearly two-week breach of the border between Gaza and Egypt, raising fears in Israel that militants from the Hamas-run territory could have entered the Jewish state through its porous 250-kilometre (150-mile) frontier with Egypt.
The Gaza-Egypt border was blown open by militants on January 23 in a bid to break a punishing Israeli blockade. It was resealed by Egyptian and Hamas forces at the weekend.
In Gaza itself, Israeli troops killed two Hamas militants during an army incursion in the south of the territory.
Militants in Gaza fired two rockets into Israel on Tuesday, with the projectiles causing damage but no injuries.