A medical source on Monday named the dead man as Ahmad Ibrahim Sari, 30, a member of Hamas's armed wing, the Izz al-Din al-Qassam Brigades. Sari's wife and child, aged six, were wounded in the same explosion, the medic said.
Abu Ubaida, spokesman for the brigades, told Aljazeera that they had opened an investigation into the incident.
He said Hamas was not accusing any group of causing the blast.
Wail al-Dahduh, Aljazeera's correspondent in the area, reported Palestinian security sources as saying an explosive device inside the house might have caused the blast.
An Israeli army spokesman said there were no Israeli military operations in the area at the time.
The explosion came hours after five other Palestinians were killed by assailants in two separate shootings in the Gaza Strip.
The attack occurred as tensions between factions in the impoverished territory deteriorated even further.
In the southern Gaza Strip town of Khan Yunus on Monday, gunmen killed a pregnant Palestinian woman and another family member and wounded her husband and his brother, a Hamas member, hospital sources said.
Fatah and Hamas fighters have
clashed in recent weeks
Witnesses said armed attackers, whose identities were unclear, opened fire at a local Hamas leader, Muhammad al-Ghalban, as he was travelling in a car with family members after dark in the town.
Al-Ghalban and his brother, who was critically wounded, were being treated at a Gaza hospital, medics said.
Sami Abu Zuhri, spokesman for the Hamas movement, said the incident was a planned attack.
"The attack targeted our mujahid [fighter] Yasir al-Ghalban. Two passengers have been killed in the car," he said.
"Some groups, mostly belonging to security services and particularly the preventative security apparatus, stand behind these incidents," he said.
The motive for the shooting was unknown, but local Hamas sources blamed rival Fatah members, and took to the streets as tensions rose.
In a separate incident in Gaza City, three bystanders were killed in the crossfire as Hamas fighters returned fire at unknown assailants, local witnesses said.
The three bystanders, all male, were pronounced dead at a Gaza hospital, medics said.
The incident took place not far from the home of Ismail Haniya, the Palestinian prime minister.
The deaths are the first since a Palestinian security officer was killed and seven were wounded in clashes between rival Fatah and Hamas factions in Gaza last Thursday, underscoring growing tension in the coastal strip.
The clashes have disrupted a tenuous peace in place since Mahmoud Abbas, the Palestinian president and Fatah's leader, and Haniya's Hamas-led government began talks last month to try to end violence in Gaza.
Meanwhile, the Israeli occupation army has carried out an arrest raid in Ramallah in the West Bank.