Israeli tanks struck Hamas military posts in the southern Gaza Strip on Tuesday night, after Palestinian militants fired a projectile into Israeli territory, media reports on Wednesday said.
This was the second such incident this week.
No injuries were reported on either side.
Despite a Qatari-brokered truce between Hamas and Israel in August, there have been several flare-ups of violence in recent months.
Israel, the United States and the European Union list Hamas as a terrorist organisation.
Hamas controls the Gaza Strip, where some two million Palestinians live in crowded, impoverished conditions.
Israel has enforced a blockade on the Strip since 2007, joined later by Egypt.
Both argue that the limits on imports are for security reasons. (dpa/NAN)