Multiple explosions targeting cars belonging to Hamas officials in the northern Gaza Strip injured two people, Palestinian security sources said.
Six explosions took place at the same time on Sunday morning in the Sheikh Radwan neighbourhood.
The wrecked cars belonged to the Palestinian resistance group Hamas, and its armed wing, Qassam Brigades.
Sheikh Radwan previously witnessed fighting between Hamas security forces and militants loyal to ISIS in early June.
ISIS had threatened Hamas in a video shared online earlier this month, vowing to end the faction's rule in the territory.
Witnesses said a freshly painted ISIS flag was seen at the site of the explosions behind the cars.
Al Jazeera's correspondent Tamer Almisshal, reporting from the scene said Palestinian authorities, closed off access to the sites.
"They [officials] have started their investigations, but so far there hasn't been a statement from the interior ministry," Almisshal said.
Hamas recently launched a fierce crackdown on alleged ISIS supporters in the coastal enclave.