TEL AVIV - Israel hit Hamas posts in the Gaza Strip on Thursday after Palestinians set off two bombs near the border fence, authorities said, with no casualties reported.
Israel's military also said it suspected based on surveillance video there was "an attempt" to fire rocket-propelled grenades toward its forces, but nothing was hit.
If confirmed, it would be the first time such weapons were used by Gaza militants against Israeli forces since a 2014 war, army spokesman Jonathan Conricus said.
A security source from Hamas, the Islamist movement which runs the Gaza Strip, said that one Israeli round hit an observation post near the border, causing damage but no casualties.
He said that earlier, shortly after sunrise, there were explosions near the border. Israel said two improvised explosive devices (IEDs) were detonated some 100 metres away from the fence on the Gaza side.
There was no immediate claim of responsibility for the blasts and Israel said it could not say who was behind it, though it held Hamas responsible as the de facto power in the Palestinian enclave.
Israel said the IEDs were detonated "toward" soldiers in a vehicle on the Israeli side of the fence near the northeastern Gaza Strip at around 6:00 am.
"It appears that there was also an attempt to fire RPG rockets toward the force," Conricus said.
"We don't have the final confirmation of that yet, but that is currently our working assumption."
Israel's army then hit what it said were four military positions in the strip belonging to Hamas and Palestinian militant group Islamic Jihad with tank fire and another with air power, Conricus said.
Israel also warned Hamas not to use civilian protests that occur near the border fence as cover to carry out attacks against its forces.
Beginning on March 30, Gazans are planning to erect hundreds of tents near the Israeli border for a six-week show of support for Palestinian refugees.
On February 17, four Israeli soldiers were wounded by an improvised explosive device on the border, sparking intense military retaliation.
Israel warplanes attacked 18 "terror targets belonging to Hamas" in Gaza in response to the blast, which severely wounded two of the soldiers, and a subsequent Palestinian rocket attack on southern Israel.
The following day, Israeli occupation forces shot dead two Palestinian teenagers near the border, Gaza medical sources said.
The Israeli army said at the time that soldiers fired "warning shots" at a number of Palestinians approaching the border fence "in a suspicious manner" but could not confirm Palestinian casualties.
Israel and Palestinian militants in Gaza have fought three wars since 2008. The strip has been under an Israeli blockade for around a decade.