TEL AVIV — As Israeli forces tightened their circle around Gaza on Tuesday, senior Israeli intelligence officials said Hamas military forces had been damaged but remained substantially intact. The intelligence officials were briefing reporters.

The assessment, which comes in stark contrast to officials’ comments on Sunday suggesting that the leadership had been damaged and that Hamas was ready to accept a truce, came as the war on Hamas entered its 18th day. The Israeli military saying its warplanes launched 60 air strikes overnight in a continued drive to destroy Hamas’s ability to fire rockets into Israel.

One target was a hotel where Hamas gunmen were said by Israel to be gathering, the military said.

Speaking in return for customary anonymity, the intelligence officials said the military wing of Hamas has been hit “to a certain extent” with “a few hundred,” Hamas fighters killed during the ground offensive that began midway through the war.

But greater damage has been done to Hamas’s capacity to run the Gaza strip, with a large number of governmental buildings destroyed over the course of the operation.

One Israeli soldier has been killed by a suicide bomber during the operations, intelligence officials said.

Hamas militants are using rockets that are Chinese-made and supplied by Iran, the intelligence officials said.

The rockets are now hitting targets that are up to 25 miles away, a longer distance than before, with some of them being smuggled into Gaza in parts and assembled inside to be shot. The officials said ranges longer than 25 miles were unlikely.

The launches have diminished, with between 70 and 80 a day before the war to between 20 and 30 now, including as many as 10 more serious grad missiles.

Under growing military pressure, Hamas fired at least two rockets into southern Israel on Tuesday, far fewer than in some recent days. The missiles struck the city of Beersheba but there were no reports of casualties.

The assessment of Hamas’s resilience came just two days after Israel’s cabinet secretary, Oved Yehezkel, told reporters that in the regular weekly cabinet meeting the heads of army intelligence and of the Shin Bet security service had said that Hamas was inclined to agree to a cease-fire, “given the harsh blow it received and given the absence of accomplishment on the ground.”

That day, another senior Israeli security official said that Hamas units were making mistakes and fighting without clear direction.

Despite international demands for a cease-fire and mounting humanitarian worries, there seemed little prospect of a respite.

Chief of Staff Lt. Gen. Gabi Ashkenazi said on Israel Army Radio on Tuesday that Israeli forces were making progress “in hitting Hamas, its infrastructure, its regime,” but said that forces yet to complete their mission. “We still have work ahead of us,” he said.

Palestinians in central Gaza City reported hearing numerous explosions on Monday night, as well as the sound of tanks moving closer to the center of the city.

The Israeli military said one Israeli officer was critically wounded and two Israeli soldiers suffered light wounds in overnight fighting. The three were hurt, the military said, after a bomb exploded in a booby trapped house that they were searching.

The fighting came amid continued diplomacy in Egypt, whose officials were talking with Hamas representatives about a possible truce.

In a televised speech on Monday night, a senior Hamas official, Ismail Haniya, expressed an openness to a diplomatic solution but reiterated previous demands that any deal include the opening of Gaza’s border crossings, which Israel and Egypt have kept mostly closed since Hamas violently pushed out its rival Fatah in 2007.

“We are not closed to this path,” he said of diplomacy, speaking from hiding in Gaza.

On Tuesday, however, Hamas said it had “substantial reservations” about an Egyptian proposal for a cease-fire in Gaza.

"There are reservations on this initiative, substantial reservations, related to the position of the resistance on the ground," a senior Hamas official Moussa Abu Marzouq told Al Jazeera television, Reuters reported from Cairo.

An Israeli official postponed a trip to Cairo on Monday. It was not clear whether he would depart on Tuesday.

Humanitarian shipments continued to flow on Tuesday. The Regional Director for the Middle East of the World Food Program, Daly Belgasmi, presided over a shipment at the Kerem Shalom crossing point. The president for the International Committee of the Red Cross, Jakob Kellenberger, visited Gaza City on Tuesday as the Israeli Army continued to press its military campaign.

Israel also said it would order a temporary lull Tuesday to permit around 100 trucks with relief supplies into the beleaguered coastal strip, one of the world’s most overcrowded places.