Cross-border clashes between Israel and Gazan armed groups reignited Wednesday little over 24 hours after Israeli airstrikes killed 15 in the blockaded Palestinian territory.
Smoke billowed from the densely-populated coastal territory after Israel claimed it was targeting rocket-launching infrastructure held by the Islamic Jihad armed group.
Sirens warning of incoming fire then blared in the Tel Aviv area, an AFP journalist reported, and in communities close to the border, according to the army.
A Gaza Health Ministry official told AFP one person was killed in the Israeli strikes, while another was seriously wounded.
An AFP journalist in Gaza saw dozens of rockets fired by Palestinian armed groups, while a senior Israeli security official told journalists "more than 60 rockets" were launched.
Israel's Magen David Adom emergency service said it received no immediate reports of casualties from the rocket fire.
According to a Health Ministry toll, the latest violence comes a day after Israeli strikes on Gaza killed three top Islamic Jihad leaders and 12 others, including four children.
Israel's military claimed Wednesday's strikes included firing on armed groups "traveling to a rocket launch site in the city of Khan Yunis" in southern Gaza.
Islamic Jihad had vowed Tuesday to retaliate, with Israel warning its residents near the border to stay near bomb shelters.
Ahead of Wednesday's fire, Gaza's usually bustling shops were closed, as resident Monther Abdullah said people "expect the worst."
"Everyone feels anxious and people aren't on the street much. I definitely feel like there's a war coming, and there's tension and fear, whether here or there (in Israel)," the 50-year-old told AFP.
The latest violence comes on the second anniversary of a devastating 11-day war fought between Gazan armed groups and Israel.
The senior Islamic Jihad operatives killed Tuesday were named as Jihad Ghannam, Khalil al-Bahtini and Tareq Ezzedine.
Although based in Gaza, the last was an armed group leader in the West Bank.
Earlier Wednesday, Israeli troops raided the West Bank town of Qabatiya, killing two people who the army accused of firing at soldiers.
The Palestinian health ministry identified the two men as Ahmed Jamal Tawfiq Assaf, 19, and Rani Walid Ahmed Qatanat, 24.
The Israeli military said troops detained one person during the raid, when soldiers were shot at from a vehicle.
Mourners including armed group members later carried the two men's bodies through the streets in a funeral procession.
Israel has occupied the West Bank since the Six-Day War of 1967 and its forces regularly operate in Palestinian cities.
Ismail Haniyeh, the chief of Gaza's ruling Hamas, said Tuesday that "assassinating the leadership" in Gaza would bring "greater resistance."
Washington, in the meanwhile, called Tuesday for "all parties to de-escalate the situation."
While Hamas has fought multiple wars with Israel in recent years, the group stayed on the sidelines of a three-day conflict fought between the country and Islamic Jihad in August.
Following Tuesday's airstrikes, Egypt – a longtime mediator in Gaza – warned such actions "inflame the situation in a way that could get out of control."
The latest violence brings to 126 the number of Palestinians killed in the Israeli-Palestinian conflict so far this year.
Nineteen Israelis, one Ukrainian and one Italian have been killed over the same period, according to an AFP count based on official sources from the two sides.