President Reuven Rivlin issued a statement, saying he was "shocked and saddened by this morning's awful terrorist attack at the Barkan industrial area".
The terrorist, in fact, was employed at one of the factories.
The army is searching for the assailant, who worked with the dead, said the official representative of the IDF. They reportedly include Mr Naalwa's brother and sister.
Jamie McGoldrick, the U.N.'s Resident Humanitarian Coordinator, said this will add a few more hours of electricity to Gaza's 2 million residents who experience daily blackouts of up to 16 hours.
The Israeli and Egyptian blockade on Gaza began in 2007, when Hamas took control of the strip from the Palestinian Authority, implemented in order to prevent military equipment and artillery from reaching terror elements like the Izz ad-Din al-Qassam Brigades, Hamas' military wing.
A manager at another company in the industrial zone, Moshe Lev-Ran, suggested the attack might not have been politically motivated. "Everybody knew him. He went upstairs to the second floor because he knew who he wanted to shoot, and he shot", he was quoted as saying by the Associated Press.
Israeli forces detained at least 8 Palestinians, including a child and former prisoners, across the occupied West Bank on predawn Tuesday.
More than 260 Palestinians have also been killed over the same period.
A wave of Palestinian attacks against Israelis, predominantly settlers, broke out in 2015, but they have since become sporadic.
The Israeli air force attacked militants in the Gaza strip, which was launched flaming balls at Israel. The settlements are considered illegal under worldwide law, though Israel disputes this.
Palestinians often face tough choices in finding employment under Israeli occupation, especially in the economically struggling West Bank.
Under the UN-brokered deal, Qatar pays for the fuel which is then delivered through Israel with United Nations monitoring, a diplomatic source said. Others have been killed in clashes with Israeli troops.