An Israeli officer was severely wounded by Palestinian fire along the Gaza border on Tuesday, just hours before a high-profile visit to the enclave by the Qatari emir, the military said.
The army did not say how the officer was hurt but a leftist Palestinian group claimed responsibility saying an explosive device was the cause.
"A soldier was severely wounded during a routine patrol along the fence in the Kissufim area," a military spokeswoman said of the incident which occurred shortly before 7:00 am (0500 GMT). Military sources said they were "checking the possibility that it was an explosive device."
The Popular Front for the Liberation of Palestine claimed responsibility for laying an explosive device which wounded an "officer in the Givati brigade," it said in a statement.
Hamas security sources said the explosion occurred as troops were mounting an incursion into Gaza territory.
"The IDF (army) will not tolerate any attempt to harm Israeli civilians, and will operate against anyone who uses terror against the state of Israel," a military statement warned.
Israeli Prime Minister Benjamin Netanyahu once again warned he would strike back at Gaza militants, which he said were supported by Tehran.
"Today we engaged in exchanges against terrorist aggression that comes from our southern border in Gaza, but it actually comes from Iran and a whole terror network that is supporting these attacks," he said on meeting Bulgarian President Rosen Plevneliev.
"The way to fight terror is to fight terror, and that we shall do with great force."
On Monday morning, Israeli troops patrolling the border came under fire from militants, prompting a series of air strikes which medics said killed two and injured another four dead and four critically wounded.
Palestinian witnesses said Monday's incident occurred after troops crossed onto the Gaza side of the border.