Locals said the Israeli strikes targeted a security facility of Hamas' military wing in Gaza City's Shuja'iyya neighborhood.
The ministry of interior in Gaza said three Hamas security officers were injured in the Israeli shelling attack, including one seriously, raising the injury count to five.
Medical official Adham Abu Salmiya said earlier that a 3-year-old boy was lightly injured by shrapnel to the head. He added that a 26-year-old man sustained moderate wounds in his foot and his hand. Both were evacuated to Ash-Shifa Hospital in Gaza City.
Hamas' military wing claimed responsibility for the mortar attacks.
The Al-Qassam Brigades said in a statement that the shelling came in retaliation to Israeli "crimes and the ongoing air and ground strikes on the Gaza Strip the latest of which targeted and killed two Hamas' fighters."
"We claim responsibility for these Jihad missions affirming that we are ready to respond to the Israeli aggression and to counter any folly by occupation with all means we have," the statement added.
For his part, Hamas spokesman Ismail Radwan said the shelling was a natural response to the ongoing Israeli strikes against the Gaza Strip. "The occupation should avoid testing Hamas' response," he said.
Israeli tanks targeted a mosque in the south, the Gaza International Airport near Rafah, and the Shokat As-Sufi village, eyewitnesses said.
The shelling came hours after huge explosions were heard in the southern Gaza City, apparently from Palestinian launch pads as resistance fighters launched mortar shells at Israeli areas bordering the Gaza Strip.
Resistance factions announced earlier that several mortar shells were launched toward the Kerem Shalom and Sofa military bases.
Israeli news outlets quoted police saying that 49 mortar shells fired from Gaza landed in Sdot Negev and Eshkol regional council. The Israeli news site Ynet reported that two Israelis were lightly injured and a building sustained serious damage.
Child injured in Israeli shelling on Gaza
Al Qassam website- Israeli occupation artillery shelled on Saturday evening number of locations in the Central area of Gaza Strip.
Eyewitnesses said that Israeli occupation artillery targeted on Saturday evening Palestinian homes near the Gaza border, what caused of massive destruction in properties and infrastructure, while number of injuries were reported among civilians as a result.
Palestinian medical sources confirmed that the Israeli shelling left five injuries among the Palestinian civilians, child was reported among the injuries.
For his role, Adham Abu Salmiyya, spokesperson of the Higher Committee of the Medical Emergency Services, stated that a three-year-old was wounded in his head, and that a 26-year-old resident was wounded in his arm and leg. Both were moved to the Al Shifa Hospital in Gaza city.