An unidentified gunman killed two people and wounded at least three others on a bustling thoroughfare in central Tel Aviv on Friday before fleeing, Israeli authorities said.
Security camera footage aired on Israel's Channel 10 television showed the assailant, who appeared to be in his mid-to-late 20s and wore protective eyeglasses and a windbreaker, browsing dried fruit at a delicatessen on Dizengoff Street. He then pulled a machine pistol from his backpack and stepped onto the pavement, shooting wildly.
With the suspect still at large, police declined to offer a motive.
"All possible angles are being investigated," spokeswoman Luba Samri said. "Large-scale police forces are conducting searches for him."
Nati Shakked, owner of the next-door Simta bar where there were several casualties, told Israel's Channel 2 TV: "It was a terrorist attack, without a doubt."
Israel has seen a wave of Palestinian street attacks since October, fueled in part by Muslim anger over stepped-up Jewish visits to Jerusalem's al-Aqsa mosque complex, also sacred to Jews, as well as the lack of any progress towards peace with Israel. The violence has been encouraged by Islamist groups that preach Israel's destruction.
There was no immediate claim by Palestinian armed groups for Friday's attack.
Israel has also been bracing for a possible attack by Islamic State, which has a small but growing following among Israeli Arabs. An Islamic State audio message circulated on social media last week threatened to strike at Israel "soon".
Israeli media showed images of an abandoned ammunition clip at the scene of the shooting that appeared to have come from a Spectre M4 machine-gun - a weapon rarely seen in Israel and the Palestinian territories.
While mob killings and lethal domestic violence are fairly commonplace in Israel, random shootings by civilians are rare.