The Israeli soldier held by Palestinian militants remains alive, an Israeli spokesman has said.
Israel has ruled out negotiations with the militants
As a deadline set by the militants passed, one of the groups holding Gilad Shalit said they would not kill him, but there would be no more talks.
The militants had given Israel until 0300 GMT to begin freeing Palestinian prisoners or face "consequences".
Israeli PM Ehud Olmert repeated refusals to negotiate and said Israel would strike "all terror elements".
Mr Olmert ordered security forces to pursue operations "against terrorists, those who protect them and those who give them orders," AFP news agency reported.
His comments came after missiles hit the Gaza Strip early on Tuesday as Israel continued air strikes for the seventh night.
The Swiss government accused Israel of breaking humanitarian law by inflicting "collective punishment" on the Palestinians.
It criticised the recent bombing of Gaza's only power plant, an attack on the Palestinian prime minister's office and the detention of several democratically-elected Hamas legislators as "unjustified".
The Israeli ambassador to Switzerland, which holds special responsibility for the Geneva Conventions, said the criticism was unfair when Israel was supplying electricity, food, water and medicine to Gaza even though Hamas was sworn to Israel's destruction.
Hamas's Izzedine al-Qassam Brigades, the Popular Resistance Committees and the little-known Islamic Army say they are holding him.
"We know that until now Gilad Shalit is alive, we know that he is injured, that he was seen by a Palestinian doctor a few days ago," Israeli government spokesman Avi Pazner told French television.
The militants have demanded that all Palestinian women and young prisoners be released along with 1,000 male prisoners in exchange for information about Cpl Shalit's welfare - a demand Israel has rejected.
SOLDIER CAPTURE TIMELINE
Sun 25 June: Cpl Gilad Shalit captured in cross-border attack
Mon 26 June: Palestinian Popular Resistance Committees demand prisoner releases in exchange for Shalit
Weds 28 June: Israeli military enters southern strip after launching air strikes on Gaza
Thurs 29 June: Israel detains dozens of Hamas officials
Sat 1 July: Groups believed to be holding Cpl Shalit demand 1,000 prisoners be released
Mon 3 July: Groups holding soldier issue ultimatum for 0300 4 July
On Tuesday morning a spokesman for the Islamic Army told the BBC: "The file is closed - there will be no more negotiations, no more information will be released, there will be no mediation."
He said "all options" were open to the militants, except killing the soldier because the captors were Muslims who did not treat their captives as others, such as the US, did.
Israel has carried out nightly air strikes against militant targets and infrastructure in Gaza. In the latest attacks, a Gaza City university was hit.
Eight militants have been killed since Israel began its military campaign to free Cpl Shalit, 19, captured nine days ago during a cross-border raid.
A small Israeli force entered northern Gaza on Monday, and tanks remain ensconced in the south. A larger force is massed on the Israel-Gaza border.
In other developments:
- Israeli troops seized three Palestinians from a police station in the West Bank town of Ramallah, where they were being held on suspicion of killing a Jewish settler last week
- A Palestinian man was shot dead in the West Bank town of Jenin. The Israeli military said it had opened fire on several people planting explosives.