The attacks on Tuesday targeted three locations in Gaza, officials told Al Jazeera.
The Israeli military said it carried out the air attacks in response to a rocket fired towards Israel.
Hamas spokesman, Hazem Qasem, rejected Israel's claims.
"The airstrikes targeted Hamas positions in the centre of the Gaza Strip," Qasem told Al Jazeera.
"The occupation claims that a group from Gaza launched rockets at them, but there is no side in Gaza that has claimed responsibility.
"We are maintaining the period of calm and did not launch any rockets. It is not beneficial for the occupation to violate this period of calm."
The emergency director at the al-Shifa hospital in Gaza, Ayman al Sahbani, told Al Jazeera that three of the injured were discharged after undergoing treatment.
"The fourth person, a 26-year-old, is in serious condition. He has a fractured skull and is unconscious in the ICU," Sahbani said.
Israel holds Hamas responsible for all fire coming out of the Gaza Strip.
For the last decade, Hamas has been the de facto government of Gaza, while the Fatah-led Palestinian Authority has controlled the West Bank.
Israel and Hamas have fought three wars since the group took control of Gaza, most recently in 2014.
Honor has just launched the Honor 9A smartphone for the global markets and the price starts from €149.90 (US$ 169.6 / Rs. 12,810). Read on to know more.
Honor has just confirmed the launch date of the company's next new 5G smartphone- Honor X10 Max on Weibo.
Realme is all set to launch its new Realme C11 smartphone with MediaTek Helio G35 SoC in Malaysia.
Realme has launched its new Nazro series smartphone- Realme Nazro 10A alongside the Realme Narzo 10 in India. The Next sale of Realme Nazro 10A will be held on June 23 via Flipkart and the Realme India website.
Vivo has just launched the company's latest smartphone Vivo V19 in India as expected.
Realme has launched the company’s latest Nazro series smartphones- Realme Nazro 10 and Nazro 10A in India.
Here is the first look of LG's new entry-level/midrange smartphone - LG Stylo 6 which was shared by reliable leakster Evan Blass.
Xiaomi India has just unveiled it's latest flagship killer- Xiaomi Mi 10 5G smartphone in India.
After several teasers and rumors, LG has finally unveiled the company's latest 5G smartphone- LG Velvet on May 7 in South Korea. The company has also revealed the pricing and availability details of the phone.
Now, LG has started pre-registration for its LG G8X ThinQ smartphone and other products as the coronavirus lockdown in India continues.